Parts of Prokaryotic &
Eukaryotic Cells
Cell Theory
1. All living things are made of
____________.
2. Cells are the basic unit of
__________ & __________ in an
organism.
3. All cells come from the reproduction
of ____________ cells.
CELL MEMBRANE MODEL
Phospholipids and
proteins move
laterally, or side to
side, for short
distances.
Proteins make a
pattern on the surface
known as the fluid
mosaic model.
NUCLEUS and NUCLEOLUS
NUCLEUS is:
Surrounded by nuclear MEMBRANE
called the NUCLEAR envelope.
Serves as the control CENTER OF
CELL
Nuclear pores allow molecules in and
out
NUCLEUS and NUCLEOLUS
CONTAINS CELL’S GENETIC
MATERIAL ( DNA)
Contains NUCLEOLUS
(Dark spot) which
makes ribosomes
(RNA)
NUCLEUS and NUCLEOLUS
– Each cell has fixed
number of chromosomes that carry
genes
– Genes control cell characteristics
Nuclear Envelope
Double membrane surrounding nucleus
Also called nuclear membrane
Contains nuclear pores for materials to
enter & leave nucleus
Connected to the rough ER
CHROMATIN & CHROMOSOMES
DNA is scrunched up as
CHROMOSOMES in DIVIDING CELLS
DNA is spread out as CHROMATIN in
NON-DIVIDING CELLS
CYTOSKELETON
Made of PROTEINS called actin and
tubulin.
FUNCTIONS:
– Helps cell maintain its shape
– Helps organelles move
around
LYSOSOMES
Sac containing digestive enzymes
FUNCTION:
Digests: food, bacteria, and worn out
cell parts for cells
Plays a role in APOPTOSIS:
“programmed cell death”
Cell suicide for the good of the
ORGANISM
LYSOSOMES
Cells take in food by
phagocytosis
Lysosomes digest
the food & get rid of
wastes
VACUOLE
STORAGE SPACE FOR:
–In plants, they store Cell Sap
–Includes storage of sugars,
proteins, minerals, lipids,
wastes, salts, water, and
enzymes
Huge in PLANT cells, small in ANIMAL
cells, NOT in BACTERIAL cells.
VACUOLE
CENTRIOLES
Bundle of microtubules made of
PROTEINS called tubulin. (9+3 ring)
Only seen in ANIMAL cells during cell
division
Function: largely unknown,
but they do assist in
cell division
CILIA & FLAGELLA
Made of PROTEINS called
microtubules– tubulin also.
organized in a “9+2”
arrangement
that help with moving cells,
in moving fluids, or in small
particles across the cell
surface
CILIA & FLAGELLA
CILIA: shorter& more numerous; look
like short “hairs”
FLAGELLA: longer & fewer; look like
“tails”; typically only 1-3 per cell.
FUNCTION (BOTH): cell movement, if
cell is non-motile, moves fluid over cell
surface Ex.- Cilia lining your windpipe
sweep mucus containing trapped
debris out of your lungs.
CILIA & FLAGELLA
Cilia Moving Away Dust Particles
from the Lungs
RIBOSOMES
Can be FREE in the cytosol or
ATTACHED to the surface of Rough ER
MADE OF rRNA (ribosomal) & PROTEIN
FUNCTION: MAKE PROTEINS
CELL MEMBRANE or PLASMA
MEMBRANE
Made mainly of PHOSPHOLIPIDS and
PROTEINS
HYDROPHOBIC “tails” of
phospholipids make molecules line up
as a LIPID BI-LAYER with POLAR heads
facing OUT and NON-POLAR tails
facing IN (to inside of bi-layer)
CELL MEMBRANE or PLASMA
MEMBRANE
Outside
of cell
Proteins
Carbohydrate
chains
Cell
membrane
Inside
of cell
(cytoplasm)
Protein
channel
Lipid bilayer
CELL MEMBRANE or PLASMA
MEMBRANE
Proteins attached to
surface (inside or
outside)= PERIPHERAL
PROTEINS
Proteins stuck into
membrane =
INTEGRAL PROTEINS
(can go part way in or
all the way through)
CELL MEMBRANE or PLASMA
MEMBRANE
Membranes are selectively permeable/
semi-permeable when they allow
certain molecules to pass through; but
keep others out.
Cytoplasm/ cytosol is the “gel-like
material + organelles” between nucleus
and cell membrane
CELL MEMBRANE or PLASMA
MEMBRANE
OTHER MOLECULES:
GLYCOPROTEINS with
attached
CARBOHYDRATE tails
to recognize self
Contain the steroid
CHOLESTEROL to
make membranes
more flexible
MITOCHONDRION (plural:
MITOCHONDRIA)
Surrounded by
DOUBLE membrane.
Contains its own
DNA.
Called the
“powerhouse” of cell
Burns food (sugars,
fats, etc) to release
energy.
MITOCHONDRION (plural:
MITOCHONDRIA)
Stores energy
released as ATP.
Smooth outer
membrane
Folded inner
membrane = CRISTAE
(increases surface area for
more chemical reactions) 
Cellular respiration happens in
the inner membrane.
MITOCHONDRION (plural:
MITOCHONDRIA)
More active
cells like
muscle cells
have MORE
mitochondria
Both plants &
animal cells
have
mitochondria
ENDOPLASMIC RETICULUM(ER)
Internal network
of hollow
membrane
tubules.
Connects to
nuclear
envelope & cell
membrane
ENDOPLASMIC RETICULUM(ER)
ROUGH ER
Rough ER has ribosomes
on its surface, while
smooth does not.
Rough ER: Attached
ribosomes make
PROTEINS which are
modified & exported.
FUNCTION ROUGH ER:
Makes membrane
proteins and proteins
for export out of cell
ENDOPLASMIC RETICULUM(ER)
Proteins are made by
ribosomes on ER
surface
They are then threaded
into the interior of the
Rough ER to be
modified and
transported
ENDOPLASMIC RETICULUM(ER)
Rough ER has
RIBOSOMES on its
surface, while
SMOOTH does not.
Is attached to the
ends of rough ER
ENDOPLASMIC RETICULUM(ER)
SMOOTH ER
FUNCTION SMOOTH ER:
Makes cell products that
are USED In the cell
Makes membrane lipids
(steroids)
Regulates calcium
(muscle cells)
Destroys toxic
substances (Liver)
GOLGI APPARATUS (BODY)
Looks like a stack of flattened sacs.
FUNCTION: Modify, sort, and package
substances from ER for transport out of cell
OR for storage.
Have a shipping side (cis face) & a
receiving side (trans face)
Receive proteins made by ER
Transport vesicles with modified
proteins pinch off the ends
GOLGI APPARATUS (BODY)
CIS
TRANS
Transport
vesicle
GOLGI APPARATUS (BODY)
VESICLES
Sacs made of membrane
Used to transport
substances within the cell–
protein from ER to Golgi to
cell membrane, or to take in
food (endocytosis) or get rid
of wastes (exocytosis)
Disposable; pinch off of and
fuse with other membranes
in the cell.
VESICLES
ENDOMEMBRANE SYSTEM
• Includes
nuclear
membrane
connected
to ER
connected
to cell
membrane
(transport)
ENDOMEMBRANE SYSTEM
CHLOROPLASTS
Surrounded by double
membrane
Has its own DNA
Outer membrane
smooth
Inner membrane sacs
called THYLAKOIDS
contain CHLOROPHYLL
where photosynthesis
happens.
CHLOROPLASTS
Stacks of
thylakoids called
GRANA. Gel like
material around
thylakoids called
STROMA.
FOUND ONLY IN
PLANT CELLS
CELL WALL
Found OUTSIDE the cell
membrane.
Provides structure & support.
Cellulose in the cell wall makes
plant cells sturdy.
Bacteria have cell walls made of
peptidoglycan instead of
cellulose.
Made of chitin in Fungi
PROKARYOTES
Bacteria are the most
common prokaryotic cell.
They do not have a
nucleus, but do contain a
single circular chromosome
made of DNA, found in the
NUCLEOID REGION.
Like all cells, bacteria are
surrounded by a cell
membrane which contains the
gel-like cytosol of the cell.
TONOPLAST
Membrane that
encloses the
CENTRAL
VACUOLE in a
plant cell,
separating it
from the
cytosol.
PEROXISOMES
Organelle containing
enzymes that
transfer hydrogen
from various
substrates to
oxygen, producing
and then degrading
hydrogen peroxide.
PLASMODESMATA
An open
channel in the
cell wall of
PLANTS
through which
strands of
CYTOSOL
connect from
adjacent cells.
CENTROSOME
Present in cytosol of all eukaryotic cells;
important during cell division; the
MICROTUBULE organizing center.