Transcript Cell Transport

Cell Transport
Organic Compounds
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Carbohydrates
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Sugars – fruits and
vegetables
Starches – potatoes,
pasta, rice, bread
Break down into
glucose (sugar) and
used to produce
energy.
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Lipids – fats, oils
and waxes
Rich in energy
Stored energy for
later use
Cell membrane –
made of lipids
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Proteins – amino acids
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H O N C
20 common amino acids
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Different amino acids
Different arrangement
Change the type of
protein formed
Meats, eggs, fish, nuts,
beans
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Enzyme – kind of
protein
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Used to speed up
chemical reactions in
the body
Each enzyme has a
special job
Ex. Saliva – speeds
up breaking down of
starches into sugar
in your mouth
How enzymes work.
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1.They are organic
proteins
2.Enzymes are specific;
they only react with
specific substances that
examples:
 Lipase (an enzyme)
will only react with
lipids(fats,oils),
 Amylase will only
react with starch,etc.
3. After they do their
job, the same
enzyme can be used
over and over again
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Nucleic acids – very
long organic substances
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CHONP
Instructs cells on
functions of life
DNA – passes down info
about organism from
parent to offspring
RNA – helps in
production of proteins
- found in nucleus and
cyto
Control of materials by cells
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Selective
permeablility –
the ability of the cell
membrane to allow
some materials in
and keep others out.
Diffusion
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As they move, they
move from higher
concentration to places
of lower concentration.
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Equilibrium Diffusion occurs
until all of the
particles are evenly
distributed.
- keep on
moving but maintain
that equilibrium
osmosis
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The diffusion of water
through the cell
membrane.
Osmosis is impt b/c
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1. Cells contain water
mole.
2. Most cells are
surrounded by water
molecules
Water moves from
higher concentration to
lower concentration
Osmosis
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Equilibrium exists
when water leaves
and enters the cells
at the same rate.
Types of transport
Passive transport –
movement of
particles across cell
membrane by
OSMOSIS
diffusion.
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- cell
does not need to
use energy to move
the particles.
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Facilitated diffusion
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Protein molecules
located in the cell
membrane help larger
molecules that normally
can’t enter the cell
membrane.
Carrier proteins
Passive transport
They act as a gate to let
lg mole into the cell
Facilitated Diffusion
Facilitated diffusion involves the use of a protein to facilitate the movement of
molecules across the membrane. In some cases, molecules pass through channels
within the protein.
Active transport
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When the cell uses
energy to pass
molecules through
cell membrane.
Movement occurs
from areas of low
concentration to
areas of high
concentration.
Carrier proteins used
Opposite of diffusion
Proteins in the Membrane
Active transport is usually done across
the cell membrane.
Embedded in the lipid bilayer are
proteins.
The proteins are very specific. One
protein that moves glucose will not move
calcium (Ca) ions. There are hundreds of types
of carrier proteins.
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Protein joins with
the particle to be
transported.
Energy from cell is
used to move the
particles.
Active transport
Endocytosis
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Some molecules are too
large to pass through
the cell membrane by
active or passive
transport.
Large proteins and
bacteria enter the cell
by becoming enclosed
in a part of the cell
membrane that folds in
to form a sphere
The sphere pinches offvacuole is made and
contents enter cyto
Exocytosis
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Substances in small
sacs are released at
the cell membrane.
The vesicle fuses
with the cell
membrane and its
contents released
from the cell.
exocytosis