Parts of a Cell
Cell Wall
Found only in plant cells
Gives support to a cell
Made of complex sugars called
cellulose
Cell Membrane
All cells have a membrane
Protective barrier that encloses a cell
In a plant cell, the membrane is JUST inside
the cell wall. In animal cells, the membrane is
the outermost layer
Contains proteins, lipids and phospholipids
Decides what goes in and out of the cellnutrients goes in, waste goes out
Protects the cell from the outside environment
Cytoskeleton
Web of proteins in the cytoplasm
Acts as a muscle and a skeleton
Keeps the membrane from collapsing
Helps some cells move
This picture shows a cell with cytoskeleton
Nucleus
Large organelle
Contains the cell’s DNA (which is information on how to make a cell’s
proteins-proteins control chemical reactions in a cell)
Nucleus is covered by two membranes
“Control center” of the cell
A nucleus could contain a nucleolus which is where a cell begins to
make ribosomes
Ribosomes
Organells that make up protein
Smallest of all organelles
Not covered by a membrane
Proteins made within the ribosomes
All cells have ribosomes
Endoplasmic Reticulum
Many chemical reactions take place here
Nicknamed ER-is a system of folded membranes in which proteins,
lipids, and other materials are made
It’s either rough ER or smooth ER
Rough ER is covered in ribosomes-usually found near the nucleus
Smooth ER makes lipids, and breaks down toxic materials that could
damage the cell
Mitochondria
Main power source of the cell
This is where sugar is broken down to produce energy
Covered by 2 membranes
Energy released by mitochodria is stores in ATP
Most ATP is made in the inner membrane of mitochondria
The are the size of bacteria
Chloroplasts
Found in plant and algae cells
Organells in which photosynthesis takes place
Have 2 membranes and their own DNA
Chloroplasts are green (because they contain chlorophyll which is a
green pigment)
Golgi Complex
Packages and distributes proteins
Looks like smooth ER
Lipids and proteins from the ER are sent to the Golgi Complex where
the lipids and proteins are assigned to do different jobs
Processes and transports proteins and other materials OUT of the cell
Vesicle
Bubble that forms from the Golgi
complex is a vesicle
A vesicle is a small sac that surrounds
material to be moved into OR out of the
cell
All eukaryotic cells have vesicles
Also move materials within a cell
Different vesicles have different jobs
Lysosomes
Vesicles responsible for digestion in a cell
Contain digestive enzymes
Destroy worn-out organelles, get rid of waste, and protect the cell from
foreign invaders
Found mainly in animal cells
Vacuoles
Another type of vesicle
In plants and fungi, some vacuoles act
as lysosomes-they store digestive
enzymes and aid in digestion
The central vacuole in plant cells store
water and other liquids
Some plants wilt when their central
vacuole loses water
Animal Cell
Plant Cell