Cell Structure
& Function
http://koning.ecsu.ctstateu.edu/cell/cell.html
Definition of Cell
A cell is the smallest unit that is
capable of performing life
functions.
Examples of Cells
Amoeba Proteus
Plant Stem
Bacteria
Red Blood Cell
Nerve Cell
“Typical” Animal Cell
http://web.jjay.cuny.edu/~acarpi/NSC/images/cell.gif
“Typical” Plant Cell
http://waynesword.palomar.edu/images/plant3.gif
Cell Parts
Organelles – inside
the cell
1. Nucleus
• Controls cell processes – contains DNA
2. Nuclear Membrane
•Surrounds nucleus
•Made of two layers
•Provides support and
protection for the
nucleus
3. Chromatin
• In nucleus
• Made of DNA +
Protein which gives
us chromosomes.
• Contain instructions
for traits &
characteristics
• (looks like cooked
spaghetti)
http://library.thinkquest.org/12413/structures.html
4. Nucleolus
• Inside nucleus
• Produces ribosomes
for the cell (pink
center in the drawing)
http://library.thinkquest.org/12413/structures.html
5.Nuclear Pores
• Holes which allow
material to move
into or out of the
nucleus.
6.Cytoplasm
• Fluid-like mixture
• Supports the cell organelles.
Endoplasmic Reticulum
• 7.Smooth type (SER):
lacks ribosomes.
Contains enzymes to
make lipids.
• 8.Rough type (RER)
(pictured): ribosomes
embedded in surface.
Lipids and proteins are
assembled for export
from the cell.
http://library.thinkquest.org/12413/structures.html
9.Ribosomes
• Each cell contains
thousands
• Make proteins
• Found on endoplasmic
reticulum & floating
throughout the cell
• VERY SMALL!!
http://library.thinkquest.org/12413/structures.html
10.Mitochondria
• Powerhouse of the cell
• Converts the energy in
food to the energy that the
cell can use (ATP).
http://library.thinkquest.org/12413/structures.html
11.Golgi Bodies
• Modify, sort and
package protein.
http://library.thinkquest.org/12413/structures.html
12.Lysosome
• Contain enzymes to
break down proteins,
fats, and carbs.
• Garbage collector of the
cell.
http://library.thinkquest.org/12413/structures.html
13. Vacuoles
• Membrane-bound
sacs for storage,
digestion, and waste
removal
• Contains water
solution
• Help plants maintain
shape
http://library.thinkquest.org/12413/structures.html
14. Chloroplast
• Usually found in plant
cells
• Converts sunlight into
plant food.
• Where
photosynthesis takes
place
http://library.thinkquest.org/12413/structures.html
15.Centrioles
• Aid in cell division
–only 2 in cell
• Only found in
animal cells.
Cytoskeleton
• 16. Microtubules – • 17. Microfilaments
maintain cell shape
– aid in movement
and help form the
and support. (solid)
spindle in cell
division. (hollow)
18. Cell Wall
• Provides support and protection for a plant
cell. Found only in plants.
19. Cell membrane
• Regulates what enters and leaves a cell
• Provides protection and support for the
cell