Transcript or Cell Membrane

Cells – The Basic Units of Life
Basic Regions of the Cell
Cytoplasm
-the cell substance between the
cell membrane and the nucleus, containing the
organelles, cytoskeleton, and various particles.
Nucleus - a part of the cell containing DNA and
RNA and responsible for growth and reproduction
The control center of the cell.
Cell Membrane - The semipermeable membrane
that encloses the cytoplasm of a cell. Also called the
plasma membrane.
Cell
Organelles
Organelles found in
Both Animal and
Plant Cells
The Plasma Membrane
(or Cell Membrane)
The semipermeable membrane that encloses the
cytoplasm of a cell.
Made up of fatty molecules
arranged in a double layer
It is selectively permeable –
meaning it lets only SOME
substances in or out. It controls
what enters and leaves the cell.
It has receptor proteins which
detect signals from outside the cell
The Nucleus
Contains all genetic information for the cell in the
form of DNA
Inside nucleus -instructions contained in the DNA are
copied into RNA.
Then the RNA leaves the nucleus and brings
instructions to the rest of cell for producing proteins
The Nuclear Membrane
Surrounds the nucleus
Composed of two layers
Has openings (pores) for
“traffic” in and out of the
nucleus.
It is attached to the endoplasmic reticulum.
Mitochondria
(singular “mitochondrion”)
Called the “Power Plants” of the cell
They convert organic materials into
energy (they make a substance called
ATP).
Carry out cellular respiration.
Sugar + oxygen  carbon dioxide + water + energy(ATP)
They control the level of water and
other materials in the cell.
A cell can have hundreds or thousands
of mitochondria, which can occupy up
to 25% of the cell's cytoplasm.
Cellular Respiration
Mitochondrion
Sugar + Oxygen  Carbon Dioxide +Water + Energy(ATP)
Takes place in the mitochondria of cells of
both animals and plants.
Ribosomes
Their function is to assemble proteins (from amino acids)
Look like little “dots”. Some on the surface of
endoplasmic reticulum and some “free” in the cytoplasm
Each cell contains thousands.
Endoplasmic Reticulum
Connected to the nuclear
membrane.
A network of tubes.
The cell’s transport system
The “rough type” has ribosomes
on its surface.
The “smooth type” lacks
ribosomes.
Help transport proteins to different parts of the cell.
Golgi Apparatus
Protein packaging
plant. Packages
molecules into
small sacs called
vesicles.These are
sent to other
parts of the cell.
Vacuole
Sacs with a membrane. Used for storage,
digestion and waste removal. Contain water
solutions. Usually one large central vacuole in
plant cells and more than one smaller vacuole in
animal cells.
Lysosomes
lysosome animation
Digestive “plant” for proteins, fats and
carbohydrates. They fuse with a food vacuole,
digest it and carry the wastes to the cell
membrane for disposal. Help keep the cell
“clean” by destroying used up organelles.
Organelles found in
Animal Cells Only
Centrioles
There is one pair in each cell.
Each centriole is made up of a
ring of nine microtubules.
During cell division, or mitosis,
the centrioles produce spindle
fibers which help to pull
chromosomes apart.
Centrioles are found only in
animal cells.
Organelles found in
Plant Cells Only
Chloroplasts
Found in all higher
plant cells.
They contain
chlorophyll, which
makes them green.
They capture light energy from the
sun to carry out photosynthesis in
the cell.
carbon dioxide + water + energy
CO2 + H2O + energy
chlorophyll
chlorophyll
sugar + oxygen
C6H12O6 + O2
The Cell Wall
Protects the cell
Makes the cell rigid (found only in plants)
Lets water and nutrients pass through (porous)
Thicker than cell membranes
Made up of cellulose and other materials
The Differences Between
Animal and Plant Cells
Animal Cells
Plant Cells
Contain centrioles
Don’t contain
centrioles
Contain chloroplasts
Don’t contain
chlorplasts
Do not have a Cell
Wall
Have more than one
small vacuole
Usually smaller than
plant cells
Have a Cell Wall
Usually have one large
central vacuole
Usually larger than
animal cells
Summary of Cell Organelles
Organelle
Function
Mitochondria
Energy center or "powerhouse" of the cell. Turns food into useable
energy (ATP)
Ribosomes
Make protein
Golgi Apparatus
Processes, packages and secretes proteins
Lysosome
Contains digestive enzymes, breaks things down
Endoplasmic
Reticulum
Transport, "intracellular highway"
Vacuole
Stores water or other substances
Chloroplast
Uses sunlight to create food, photosynthesis (only found in plant cells)
Cell Wall
Provides additional support (plant and bacteria cells)
Cell membrane
Gives form to cell and controls materials going into and out of cell
Nucleus
Direct cell activity and forms ribosomes
Centrioles
Organize spindle fibers and assist mitosis
Plastids (like
chloroplasts)
Pigment-forming structures providing color.
Some other
structures found
in Cells
Cilia (singular cilium)
Thin, tail-like projections
coming from the outer surface
of the cell.
One type is used for propulsion.
Another type used for sensing.
cilia
cilia animations
Found in protozoa (propulsion)
Found in cells lining our
trachea (sweep mucus) and
ovum (move ovum from ovary to uterus)
Flagella (singular flagellum)
A “whip-like” organelle used to move
about. Used by many unicellular
organisms mainly. (eg. bacteria)
flagella animations