Cell Structure
& Function
Cell Theory
• All living things are made up of cells.
• Cells are the basic unit of structure and
function in living things.
• All cells are produced from other cells.
Definition of Cell
A cell is the smallest unit that is
capable of performing life
functions.
Two Types of Cells
•Prokaryotic
•Eukaryotic
Prokaryotic
“An organism whose cells lack a
nucleus and some other cell structures.”
• Do not have
structures
surrounded by
membranes
• Few internal
structures
• One-celled
organisms,
Bacteria
Eukaryotic
“An organism whose cells contain nuclei.”
• Contain organelles surrounded by membranes
• Most living organisms
Plant
Animal
“Typical” Animal Cell
“Typical” Plant Cell
Cell Parts
Organelles
Cell Membrane
• Outside cell boundaries
that controls which
substances can enter or
leave the cell.
• Double layer
Cell Wall
• A rigid layer of
nonliving material that
surrounds the cells of
plants and some
other organisms.
• Supports & protects
cells
• Surrounds cell
membrane
Inside the Cell
Nucleus
• The control center of a eukaryotic cell that directs the
cell’s activities and contains the information that
determines the cell’s form and function.
• Separated from cytoplasm by nuclear membrane
• Contains genetic material - DNA
Nuclear Membrane
• Surrounds nucleus
• Made of two layers
• Openings allow
material to enter and
leave nucleus
Chromosomes
• In nucleus
• Made of DNA
• Contain instructions
for traits &
characteristics
• A doubled rod of
condensed chromatin
Nucleolus
• Inside nucleus
• Contains RNA to build
proteins
Cytoplasm
• Gel-like mixture
• Surrounded by cell membrane
• Contains hereditary material
Endoplasmic Reticulum
• A cell structure that forms
passageways in which
proteins and other
materials are carried
through the cell.
• Smooth type: lacks
ribosomes
• Rough type (pictured):
ribosomes embedded in
surface
Ribosomes
• Grain-like
• Makes proteins
• Some attach to
endoplasmic
reticulum;
others float in the
cytoplasm
Mitochondria
• Rod-shaped cell structures that
convert energy in food molecules to
energy the cell can use to carry out its
functions.
• Produces energy through chemical
reactions – breaking down fats &
carbohydrates
• Controls level of water and other
materials in cell
• Recycles and decomposes proteins,
fats, and carbohydrates
Golgi Bodies
• Protein 'packaging
plant‘
• Move materials within
the cell
• Move materials out of
the cell
Lysosome
• Small, round structures
containing chemicals
that break down certain
materials.
• Digestive 'plant' for
proteins, fats, and
carbohydrates
• Transports undigested
material to cell
membrane for removal
Vacuoles
• Membrane-bound
sacs for storage,
digestion, and waste
removal
• Contains water
solution
• Help plants maintain
shape
Chloroplast
• Usually found in plant
cells
• Contains green
chlorophyll
• Where
photosynthesis takes
place
Compare and Contrast Plant and
Animal Cells
Animal Cells
*Cell membrane
*Cytoplasm
*Vacuoles
*Nucleus
Plant Cells
*Cell Wall
*Cell Membrane
*Cytoplasm
*Vacuoles
*Chloroplasts
*Nucleus