Download Cell Structure

Cell Structure
Characteristics and Functions
Plasma (cell) Membrane
(this refers to the
membrane that
surrounds the cell)
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Nucleus
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Nucleolus
Nuclear Envelope
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Stores DNA of a cell. (In a non-dividing cell,
the DNA is in the form of chromatin)
Contains Nucleolus
Surrounded by nuclear envelope
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Site for ribosome subunit production
It is found within the nucleus
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Ribosomes (free &
bound)
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Vesicles
Smooth ER
Rough ER
Golgi Apparatus
Lysosomes
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Vacuoles
Regulates material entering and leaving the
cell (selectively permeable)
Made of phospholipids
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A double-membrane (2 phospholipid
bilayers) that surrounds the nucleus
Regulates material entering and leaving the
nucleus (selectively permeable)
Contains nuclear pores to allow things in and
out the nucleus.
Sole function is to make proteins.
They are made of proteins and rRNA
Consists of 2 subunits (large and small)
Free ribosomes are suspended in the
cytosol/cytoplasm and predominantly make
polypeptides (proteins) needed by the cell.
Bound ribosomes are attached to Rough
Endoplasmic Reticulum (ER) predominantly
make polypeptides (protein) to be exported
(secreted) from the cell
Membrane sacs that transport material
throughout the cell.
Labyrinth of membrane-bound tubes and sacs
Synthesize lipids
Breakdown carbs
Detoxification (liver cells have extensive
smooth ER)
Labyrinth of membrane-bound tubes and sacs
Contains ribosomes that primarily make
polypeptides (proteins) for export / secretion
Looks like a stack of pancakes
It packages, stores, and ships material
(proteins) from the ER to the cell membrane
to be exported from the cell
Membrane-bound sacs that contain hydrolytic
enzymes used to digest/breakdown material
The enzymes must be “locked” in the sac so
that they don’t degrade the cell.
Digest biological things for the cell (food, old
organelles, bacteria)
White blood cells have a lot
Some non-plant cells have food vacuoles to
store/hold food/nutrients.
Plant cells have a central vacuole which is
primarily used to store water.
Animal
Cell
Plant Cell
Bacteria
Yes
yes
yes
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yes
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yes
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yes
YES
Free In
cytoplasm
only! no
ER
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yes
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Yes
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NO
Yes
Yes
(this is
debatable)
NO
Yes
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Yes
(some)
No
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Mitochondria
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Chloroplasts
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Peroxisomes
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Cytoskeleton
 Microfilaments
 Microtubules
 Intermediate
filaments
Centriole/centrosome
(2 centrioles make up
centrosome)
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Cilia/Flagella
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Cell Wall
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Many unicellular cells have a contractile
vacuole to regulate internal water.
In plants helps with turgor pressure
Organelle where cellular respiration occurs.
Oxygen is used to make ATP from
macromolecules (glucose)
Has a double membrane (2 phospholipid
bilayers)
The inner membrane has many folds (cristae)
to increase surface area for respiration.
Has its own DNA
Get from your mother
Organelle where photosynthesis occurs.
Also has a double membrane.
Contains stacks of thylakoids (grana)
Thylakoids hold the pigments site of light
reactions
Stroma surrounds the thylakoids and is the
site of the Calvin Cycle.
Calvin Cycle makes sugar (fueled by ATP
and NADPH from light reactions)
Has its own DNA
Membrane sacs with enzymes that breakdown
toxic substances. (chemicals, pesticides, etc)
The reactions make peroxide H2O2
Catalase is then used to breakdown the
peroxide
Provide shape and support for cells
Microtubules also serve as “tracks” for
structures to move across the cell
Spindle fibers move chromosomes during
Mitosis, Meiosis
Barrel shaped structure made up of
microtubules
Used during cell division to produce mitotic
spindle (spindle fibers)
Cilia are hair-like structures
Flagella are whip-like structures
Cilia found in our respiratory tract
Flagella found in sperm
Unicellular organisms use for movement
Provides shape, support, and protection for
plant cells, bacterial cells
Primarily made of cellulose (in plant cells)
Yes
Yes
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yes
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yes
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yes
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Yes
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No
Yes
(some)
Yes
(some
sperm cells)
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Yes
Yes