Slide 1

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 2

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 3

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 4

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 5

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 6

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 7

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 8

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 9

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 10

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 11

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 12

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 13

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 14

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 15

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 16

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 17

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 18

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 19

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 20

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 21

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 22

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 23

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 24

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell


Slide 25

Cellular
Transport
OrHow do I
get in and
out of here?

Cells need to:
• Move nutrients into the cell
• Remove waste products
from the cell
• Export products made for
other parts of the organism
(hormones, enzymes,
neurotransmitters, etc.)
• Control the concentration
of materials inside the cell.

The Cell Membrane:
Controls what enters and
leaves the cell

Is Semi permeable –
allows some molecules
to move freely through,
but keeps others out

Three Ways to Move In/Out of a Cell:
• Passive Transport
• Active Transport
• Bulk Transport

Passive Transport
• The cell does not need
to use any energy
• Movement of materials
is from an area of
high concentration
to an area of
low concentration
(molecules spread out)
• Molecules move with
the concentration
gradient

High

Low

Passive Transport - Diffusion
Movement :
• Occurs until equilibrium is achieved
• Caused by random motion of molecules

Diffusion is Affected by:
•Temperature
Faster at higher temperatures

•Molecular weight
Lighter molecules move faster

•Concentration gradient
Faster when gradient is high

Can diffusion happen through the cell
membrane?
YES, as long as the particles are small
enough and not charged

Small, non charged molecules and water can move
between the phospholipid molecules of the membrane.
This includes: carbon dioxide, oxygen,
alcohol, glycerol

Passive Transport:
Facilitated Diffusion
• Substances helped
into the cell by
channel proteins
– Polar molecules such
as glucose
– Ionic molecules such
as amino acids

• Still does not use any
cellular energy.

Transport
Protein

Diffusion vs. Facilitate Diffusion

What happens when the particles are too big to cross
the membrane and there are no protein channels?
Large
Molecules

Large
Molecules

osmosis

Water Moves

Passive Transport: Osmosis
• The movement of WATER across a
differentially permeable membrane
– Solutes can not move across membrane
but water can
– Water moves from an area of high water
concentration to low water concentration
– Water diffuses towards the higher
concentration of solute.

Three Concentration Situations:
Isotonic:
a solution that has an equal solute
concentration to a neighboring
solution.

Hypertonic:
a solution that has a relatively higher
solute concentration.

Hypotonic:
a solution that has a relative lower
solute concentration.

Water moves towards the higher
solute concentration:

What does this
mean to a cell?
The water content of
the cell will be
affected by the
concentration of
solutes around and
in the cell.

Isotonic

No net movement of
water in or out of cell

Hypertonic

Plasmolysis
occurs – cell
shrinks as
water leaves

Hypotonic

Water enters the
cell. If too much
water enters the
cell will burst

Plants have a cell wall to protect from bursting.
Vegetables are crisp when they hold a lot of water and wilt when they lose it.

Active Transport

Active Transport: Energy Required
Transports against the concentration gradient (low to high)

Transport protein
uses energy (ATP) to
change shape

Transport protein
able to move
molecule in or out
of cell

Molecule is moved to
increase the
concentration
gradient

Active Transport: Nerve Cells

Bulk Transport
• Macromolecules are too large to move with
membrane proteins and must be
transported across membranes in vesicles.
• The transport of macromolecules out of a
cell in a vesicle is called exocytosis.
• The transport of macromolecules into a cell
in a vesicle is called endocytosis.

Exocytosis –
molecules leave the
cell when the vesicle
fuses with the
membrane

Endocytosis –
molecules brought
into the cell by
infolding the
membrane and
forming a vesicle

Bulk Transport
• If the material taken up by
endocytosis is a large particle it
is called phagocytosis.
• If the material taken up by
endocytosis is a liquid or small
particle it is called pinocytosis.
• Receptor-mediated endocytosis
is a selective, highly efficient
form of endocytosis.

Bulk Transport: Receptor Mediated

Receptor attaches to a specific
molecule and moves it into the cell