7.2 Cell Structure Notes
Prokaryote v. Eukaryote
Plant v. Animal
Structure
Name: ______________________________________________________________
Prokaryote
or
Eukaryote?
1. Cell Membrane/ Plasma Membrane
Both
2. Cytoplasm & Cytosol
Both
3. Nucleus
Eukaryote
Nickname/Location
Function
City Analogy
Selectively permeable membrane that
surrounds the cell. It allows some things in
and some things out of the cell (ex: water and
salts) to maintain homeostasis inside the cell.
it is made up of a phospholipid bilayer and
proteins.
Fence around the city
The cytoplasm is often mistakenly referred to
as the fluid portion of the cell. However, it
really just means the inside of the cell (from
the plasma membrane to the nuclear
membrane). The jelly-like fluid where the
organelles float around is actually called the
cytosol and is made up of mostly water.
The space inside the city
from the fence to city hall.
It contains most of the cell's DNA. DNA
contains the instructions for the making of
proteins. Recall that DNA is an example of a
nucleic acid. When DNA is in the loose form
it is called chromatin and when it is condensed,
it is called a chromosome. The nucleus also
contains the nucleolus.
City Hall
Contains DNA, protects it from damage and is
not visible when the cell is dividing.
4. Nuclear Membrane/ Nuclear
Envelope (see in image above)
Eukaryote
Made of 2 membranes, it surrounds the
nucleus. It contains thousands of holes called
nuclear pores that allow substances to enter
and exit the nucleus.
Outer shell of the nucleus
Fence around city hall
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Structure
Prokaryote
or
Eukaryote?
5. Chromosomes/ DNA/ Chromatin
Both
Nickname/Location
Function
Chromosomes are made up of DNA and
proteins. They have bands on them called
genes. DNA is found primarily inside the
nucleus and it carries the instructions for the
making of proteins.
City Analogy
The instructions to run the
city
Genetic blueprint for protein. Is known as a
double helix due to its twisted ladder shape.
6. Nucleolus
Found inside the nucleus, this is where
ribosomes are created.
Eukaryote
7. Ribosomes
(the black dots
on the rough
endoplasmic
reticulum shown
at the right)
8. Endoplasmic Reticulum (Smooth and
Rough)
Both
Proteins (like enzymes) are assembled on
ribosomes. Ribosomes are small particles
made up of RNA and proteins. They are either
attached to the ER or free floating in the
cytosol.
Protein factory that is made up of RNA.
Eukaryotes
Found throughout the cell and made up of sacs
filled with fluid and enzymes. Smooth ER
does not have ribosomes. Lipids are
assembled, carbohydrates are metabolized, and
drugs are detoxified on the smooth ER.
Fluid filled tunnel.
Smooth ER- River that
runs through the city- no
boats on the river.
Rough ER- River with
boats.
Rough ER has ribosomes. Proteins are
assembled and folded on the rough ERProtein production.
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Structure
9. Golgi Bodies/ Golgi Apparatus/ Golgi
Complex
Prokaryote
or
Eukaryote?
Eukaryotes
10. Mitochondria
Eukaryotes
Nickname/Location
Function
City Analogy
Looks like a stack of pita bread. Proteins leave
the rough ER and arrive at the Golgi. The
Golgi modifies the proteins, sorts them, and
ships to a location either inside the cell or
outside the cell using the cell vesicles.
Post office- proteins sent
off to where they belong
Makes energy for the cell called ATP by taking
in O2. They are surrounded by 2 membranes
and contain their own DNA. Mitochondria are
inherited from your mom (maternal side).
A generator, sending out
energy
Cell powerhouse where cellular respiration
takes place (releases energy stored in food).
11. Cytoskeleton (Microtubules and
Microfilaments)
Eukaryotes
Maintains the cell's shape and is involved in
moving organelles and the entire cell. Keeps
organelles in place. It is used during cell
division.
Microtubules are large, hollow, and made of a
protein called tubulin.
Microfilaments are think, flexible and made of
protein called actin.
12. Vacuole
Both
Stores materials like water, salts, and
proteins. Plants have a large central vacuole
with mostly water, dissolved minerals, and
wastes inside it. Unicellular organisms (like
amoeba) contain contractile vacuoles that
pump excess water from the cell. Animals
have food vacuoles that fuse with a lysosome.
The small organelles that are used to store
water, waste, or food in the cell.
Water tower
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Structures Found ONLY in Animal Cells:
Structure
Nickname/Location
Function
City Analogy
13. Lysosomes
Organelle that is filled with hydrolytic/digestive
enzymes that is used to speed up the breakdown of large
food particles, macromolecules, waste, and even cells if
need be. They recycle organelles so they can be used
by the rest of the cell.
Recycling center, garbage
truck
14. Centrioles
Made of microtubules, centrioles are involved in cell
division. They are always at a right, 90 degree angle.
Large bundle of proteins that help with cell division
and organize the cell. They look like twizzlers!
15. Flagella or Cilia
Made of microtubules these projections enable cells to
move through a liquid. This is called motility or
locomotion.
Paddles (how to row a
boat)
Flagella- Long, hair-like projections located on the
outside of the cell. They move in a wave-like motion.
Cilia- Short projections located on the outside of the
cell. Moves in a whip-like motion.
Structures Found ONLY in Plant Cells:
Structure
Nickname/Location
16. Chloroplasts (Plastids)
Function
City Analogy
Captures solar energy to make food for the plant in the
process of photosynthesis. They are made of three
membranes, contain its own DNA and also contains the
green pigment called chlorophyll.
Solar panel
Traps solar energy turning it into glucose.
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17. Cell Wall
Supports, shapes, and protects the cell. Porous (has
holes) enough to allow water, oxygen, and carbon
dioxide to pass through easily. In plants, the cell wall is
made of the complex carbohydrate called cellulose.
An additional fence
It is a rigid structure. It keeps extra water out of the
cell, provides protection, and helps to keep the cells'
shape.
Path of a Protein
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