Basic Cell
Structure
Cell Membrane
a thin layer of lipid and protein that separates the
cells contents (insides) from its environment
(outsides).
**The cell membrane controls what enters and leaves
the cell.
Also called the plasma membrane.
Cytoplasm
• a semi-fluid substance
made mostly of water
and organic
compounds that is
found between the cell
membrane and the
nucleus.
• Organelles are
suspended in the
cytoplasm.
Organelles
• Structures that perform specific
functions within a cell
• “little organs”
Cytoskeleton
• a network of protein
fibers and tubes that
extend throughout
the cytoplasm. This
network gives the
cell support and
helps to maintain or
change its shape.
Nucleus
• The control center of a
cell. It is the most
easily seen of the cells
organelles.
• The nucleus contains
most of the cells genetic
material.
• It is surrounded by a
double membrane called
a nuclear membrane or
nuclear envelope.
Chromosomes – located in the nucleus, the cells
genetic information – DNA (nucleic acids)
Nucleolus – a dense portion of the nucleus
where ribosomes are made.
Ribosomes
• Small organelles that help assemble amino acids
into protein chains. They are found floating in the
cytoplasm and attached to membranes.
• Both eukaryotes and prokaryotes have ribosomes.
Endoplasmic reticulum (ER)
• A large network of membranes that
produce materials for the cell
There are TWO types of Endoplasmic reticulum
• Rough ER – has
ribosomes on its
surface and functions
in the synthesis
(making) of proteins
• Smooth ER – Makes
lipids, processes
carbohydrates and
toxic waste.
Golgi Apparatus
• a series of flat,
membrane-bound
sacs that sorts,
packages, and
transports
substances in the
cell.
• Vesicle = sac
containing
manufactured
materials
Mitochondria
• Energy producing organelles. They
change energy stored in food compounds
into energy usable by the cell (ATP).
Lysosomes
• Saclike organelles that contain digestive
enzymes to break down macromolecules
(such as proteins) or old organelles.
• Mostly found in animal cells
Cilia
• short, hair-like projections that are found in
large numbers on the surface of certain cells.
• Function in movement
Flagella
• A long, tail-like projection
used in movement.
Put it all together!
Plant vs Animal Cells
Cell Wall
• Plant cells have a cell wall that
is a tough rigid outer covering
that protects the plant cell and
helps it maintain its shape. It is
composed mostly of cellulose.
Fungi, algae, and bacteria also
have cell walls.
• **Animal cells DO NOT have
cell walls.
Chloroplast
• structures that enable the plant to make sugar
through photosynthesis. Contain chlorophyll
(a pigment) that gives the plant cell its green
color.
Vacuole
• All plant cells contain a large
central vacuole – a membrane
bound compartment that serves
many functions. The main
function is the absorption of
water, but they also may store
proteins, ions and waste
products.
• Animal cells may have
vacuoles, but they are very
small.
Centriole
• Animal cells also
have centrioles –
small cylinder shaped
organelles that help
move chromosomes
during cell division.
• NOT found in plants