Transcript Lecture 4 The Cell: Theory, Membranes & Organelles Cell Diagram: College of Dupage.

Lecture 4
The Cell: Theory,
Membranes & Organelles
Cell Diagram: College of Dupage
Size of Living Things
1 m = 100 cm = 1,000mm = 1,000,000 µm = 1,000,000,000nm
1mm = 1000 µm = 1000000nm
1 µm = 1000nm
Diagrams:
LargeDiagram : http://www.cellsalive.com/howbig.htm
RelativeScale : Created by TimVickers, vectorized by Fvasconcellos
The Cellular Level of Organization
Living things are constructed of cells.
Living things may be unicellular or multicellular.
Cell structure is diverse but all cells share common characteristics.
Cells are small so they can exchange materials with their surroundings.
Surface area relative to the volume decreases as size of cell increases.
- limits the size of cells
_____ ________ states:
- All organisms are composed of one or more cells.
- Cells are the basic unit of structure and function in organisms.
- All cells come only from other cells.
Signal Transduction
•
To survive, an organism must constantly adjust its
internal state to changes in the environment.
•
Must be able to receive and transmit signals,
communications to coordinate activities.
•
These may be in the form of chemicals, such as hormones or nutrients, or may take another form,
such as light, heat, or sound.
•
This communication not simple, Signal sets off chain of events that may involve several or even
dozens of steps.
•
As the signal moves through these steps, it may be transduced, or changed in form.
•
________ _______________ refers to the entire set of pathways through which environmental
signals are received and responded to by single cells.
•
Especially important in multicellular organisms…must coordinate the activities of hundreds to
trillions of cells.
•
Examples: Skin growth, Cell division.
Images:
Cell, College of DuPage
Signal Transduction, Audre Geras
CYTOPLASM
Nickname: The Matrix
Function: "molecular chowder"
in which the organelles are
suspended
Inside the plasma membrane,
the nucleus is surrounded by
cytoplasm.
A water-like substance that fills cells.
Consists of _________ and __________
________, except for the cell nucleus.
Cytosol is made up of water, salts,
organic molecules and many enzymes
that catalyze reactions.
Cell Diagram: College of DuPage
CYTOSKELETON
Nickname: Scaffolding & Highways
Functions: Multiple
Maintains cell _________
Protects the cell
Enables some cell ________ (using structures
such as flagella and cilia)
Plays important roles in intra-cellular transport
(the movement of vesicles and organelles)
Plays important role in cellular ___________
Images:
Cell, College of DuPage
Fluorescent Cells NIH Pub Domain
Cytoskeleton Diagram, Audesirk, Teresa and Gerald, Biology, Prentice Hall, 1999
Network of protein fibers running throughout the cytoplasm
that give a cell its shape & provide a basis for movement.
Micro__________
Two intertwined strands of actin protein.
Cell movement, cell shape, cytoplasmic streaming,
cell divisionholding the cell together.
Microfilaments,
Intermediate Filaments
& Microtubules
____________ Filaments
Fibrous proteins supercoiled into thick cables
Cell shape, anchoring nucleus to other organelles
Micro____________
Hollow tubes of tubulin
Cell shape, cell movement, chromosome movement during division.
“Highways” along which the organelles travel and are conveyed.
Microtubules may work alone, or join with other proteins to form more complex structures called cilia, flagella
or centrioles .
Image:
www.bact.wisc.edu/Microte
xtbook/index.php?mod...
Centrioles & Centrosomes
The _____________, also called the "microtubule organizing center", is an area in the
cell where microtubles are produced.
Within the cells of animals are a pair of ___________, made of nine sets of triplet
microtubules.
Microtubules >
Centriole > Centrosome
Images:
Cell, College of DuPage
Centrioles, Pearson Education Benjamin Cummings
_______ & _____________
• External appendages from
cell membrane
• Aid in locomotion of the
cell.
• Internal structure consists
of microtubules.
• Motility > coordinated
sliding movements of
microtubules.
Images:
Cell, College of DuPage
Cilia Structure, Mariana Ruiz
SpermEgg, Tronicum Wiki
ORGANELLES
Animal and plant cells
have organelles.
Organelles
compartmentalize
functions within the
cell.
The organelles of animal and plant cells are similar to each other
except that __________ are present only in animal cells, and
___________ are present only in plant cells.
Image: Mariana Ruiz
Organelles: ___________
Nickname: Protein factory
Function: Make proteins
Can be found alone in the
cytoplasm, in groups called
polyribosomes, or attached
to the endoplasmic
reticulum.
Images:
Cell, College of DuPage
Ribosome, pub dom anonymous
RibosomeTranslation,
http://www.studiodaily.com/main/searchlist/6850.html
Organelles: Energy-Related
____________
Found in
plants &
animals
&
____________
Both organelles house energy
in the form of ATP.
Not found
in animals
Both ancestrally were
independent cells that formed a
symbiotic relationship with other
cells.
Images:
Mitochondria, Mariana Ruiz
Chloroplast Ollin Wikipedia
ENERGY-RELATED ORGANELLES:
Mitochondria
Nickname: The Powerhouse
Function: Energy formation
Breaks down food to make ATP
ATP: is the major fuel for all cell activities that require energy
Bound by a double membrane surrounding fluid-filled matrix.
The inner membranes of mitochondria are __________.
The __________ contains enzymes that break down carbohydrates and the cristae house
protein complexes that produce ATP.
Image: Mariana Ruiz
ENERGY-RELATED ORGANELLES:
Chloroplasts
A chloroplast is bounded
by two membranes
enclosing a fluid-filled
stroma that contains
enzymes.
Membranes inside the
stroma are organized into
thylakoids that house
chlorophyll.
___________ (a green
pigment) absorbs solar
energy and carbohydrates
are made in the stroma.
Image: Ollin Wiki
System of internal membranes within eukaryotic cells that divide the cell into
compartments, or organelles.
Transport system, for moving molecules through interior of cell, as well as interactive
surfaces for lipid and protein synthesis.
Membranes of the endomembrane system are made of a lipid bilayer, with proteins.
The endomembrane system
consists of:
1. ________ ________
2. __________ ________
3. ______ _______
4. __________
5. __________
6. _________ ___________
Image: Mariana Ruiz
ENDOMEMBRANE SYSTEM ORGANELLES:
Nucleus
Nickname: Control Center
Function: Separates the genetic
material (DNA) from the rest of
the cell.
DNA, the genetic material, is a
blueprint, or code for making
proteins.
Parts of the nucleus:
• _________ ___________
- double membrane structure
that separates nucleus from
cytoplasm.
•
____________ - semifluid
medium inside the nucleus.
•
________ – DNA and proteins.
•
________ – Chromatin and
ribosomal subunits.
Images: Mariana Ruiz
ENDOMEMBRANE SYSTEM ORGANELLES :
Endoplasmic Reticulum
Nickname:
Manufacturers
Function: Internal
production &
delivery system of
the cell.
System of membranous
channels and saccules (a small
sac).
________ is studded with
ribosomes. Site of protein
synthesis and processing.
________ lacks ribosomes. Site
of synthesis of phospholipids
and packaging of proteins into
vesicles.
ENDOMEMBRANE SYSTEM ORGANELLES :
_________ ___________
Nickname: The Shippers
Function: Packages,
modifies, and transports
materials to different location
inside/outside of the cell.
Appearance: Stack of
pancakes
Consists of a stack of curved saccules.
Receives protein and also lipid-filled
vesicles from the ER, packages, processes,
and distributes them within the cell or for
export out of the cell (secretion).
Also encloses digestive enzymes into
membranes to form lysosomes.
Images:
Micrograph, Louisa Howard
Diagram, Mariana Ruiz
ENDOMEMBRANE SYSTEM ORGANELLES:
_____________
Nickname: The Packages
Function: Store,
transport, or digest cellular
products and waste.
Small compartments separated from
the cytosol by at least one lipid
bilayer.
Made in Golgi apparatus, ER, or from
parts of the plasma membrane.
Vesicles form while taking in
(____________) or discharging
(____________) materials.
Image: Mariana Ruiz
ENDOMEMBRANE SYSTEM ORGANELLES:
_______________
Nickname: Clean-up crew
Function: Break down food into
particles the rest of the cell can use
and to destroy old cells
Vesicles produced by the
_________________.
Contain hydrolytic enzymes
and are involved in intracellular
digestion.
Image:
http://www.people.virginia.edu/~rjh9u/lysosome.html
Plasma Membrane
What is it?
What is it made of?
What is its function?
Diagrams:
Prokaryotic Cell, Mariana Ruiz
Membrane: NIST
Prokaryotes – Plasma Membrane as a Barrier
____________________ MEMBRANE
Primary function of plasma membrane → regulate movement
of molecules entering or leaving cell.
Movement of molecules across plasma membrane requires
energy.
______________ TRANSPORT
Movement of molecules is passive if no energy sources of the
cell are expended.
_____________ = when molecules move from a higher to a
lower concentration.
What type of things might affect the rate of diffusion?
Diffusion Animation: biologycorner.com
Plasma Membrane as a Barrier
PASSIVE TRANSPORT (Continued)
_________ Diffusion
Proteins assist in diffusion of molecules across plasma membrane.
Movement only occurs in the presence of a concentration gradient.
Some molecules move across the membrane more quickly if diffusion is facilitated by a
carrier molecule.
Images:
Cell: College of DuPage
Facilitated diffusion, Mariana Ruiz
Plasma Membrane as a Barrier
Osmosis
Diffusion of ________ across the plasma membrane.
Environment surrounding cells may contain amounts of
dissolved substances (solutes) that are…
equal to
less than
greater than
…those found within the cell.
Tonicity
_________: no net movement of water
between cell and environment
_________: a higher concentration of solute.
_________: a lower concentration of solute.
Water will always move toward a hypertonic
environment!!
Diagrams:
Cell: College of DuPage
Osmosis - www.scienceaid.co.uk/biology/plants/osmosis.html
Blood Cells: Mariana Ruiz
Plasma Membrane as a Barrier
__________ Transport
How most molecules move across the plasma membrane.
Analogous to a pump moving water uphill.
Types of active transport are classified by type of energy used to drive molecules across
membranes.
ATP Driven Active Transport
Energy from adenosine triphosphate (ATP) drives substances across the plasma membrane with
the aid of carrier molecules.
Diagram:
Cell, College of DuPage
We hope that you enjoyed
your trip through the
endomembrane system!
Endomembrane System
Have
a
nice
day!
1. Nuclear envelope
2. Endoplasmic reticulum
3. Golgi apparatus
4. Vesicles
5. Lysozomes
6. Plasma Membrane
http://www.mises.org/images4/stewardess.jpg
Now let’s
talk about
some
more
structures
found in
PLANT
Cells!!
•
ENERGY-RELATED ORGANELLES:
Chloroplasts
A chloroplast is bounded
by two membranes
enclosing a fluid-filled
stroma that contains
enzymes.
Membranes inside the
stroma are organized into
thylakoids that house
chlorophyll.
Chlorophyll (a green
pigment) absorbs solar
energy and carbohydrates
are made in the stroma.
Image: Ollin Wiki
PLANT CELL: _____________
Figure 7-5 Plant and Animal Cells
Section 7-2
Please
water
me!
Nickname: Reservoir
Function: Stores water
- This is what
makes lettuce
crisp.
- When there is no
water, the plant
wilts.
Images:
Go to
Section:
Photomicrograph Plant Cell,
biology.unm.edu/.../Summaries/Cell.html
Osmosis Plant Cell, Mariana Ruiz
PLANT CELL: ______ __________
Function: Provides
support and protection to
the cell membrane
Found outside the cell
membrane in plant cells
Image: Mariana Ruiz
Animal Cell (Eukaryote)
Image: Mariana Ruiz
Unlabeled Animal Cell
Image: MesserWoland and Szczepan1990
Plant Cell (Eukaryote)
Image: Mariana Ruiz
Cells Alive Demo
http://www.cellsalive.com/cells/cell_model.htm
Key to Blanks
P3: cell theory
P4: signal transduction
P5: cytosol, cellular organelles
P6: shape, movement, division
P7: filaments, intermediate, tubules
P8: centrosome, centrioles
P9: cilia, flagella
P10: centrioles, chloroplasts
P11: ribosomes
P12: mitochondria, chloroplasts
P13: cristae, matrix
P14: chlorophyll
P15: nuclear membrane, endoplasmic reticulum, golgi apparatus, vesicles, lysosomes, plasma
membrane
P16: nuclear membrane, nucleoplasm, chromatin, nucleolus
P17: rough, smooth
P18: golgi apparatus
P19: vesicles
P20: lysosomes
P22: semi-permiable, passive, diffusion
P23: facilitated
P24: water, isotonic, hypertonic, hypotonic
P25: active
P29: vacuole
P30: cell wall