Download Cell Structure and Function

Cell Structure
and Function
Definition of Cell
• A cell is the smallest unit that is capable of
performing life functions.
Prokaryotic Cells
• Do not have
structures surrounded
by membranes (no
nucleus)
• Few internal
structures
• Single-celled
organisms, Bacteria
Eukaryotic Cells
• Contain organelles surrounded by
membranes
• Most living organisms (plants and animals)
Plant Cell
Animal Cell
http://library.thinkquest.org/C004535/eukaryotic_cells.html
“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: tiny cell structures that have
specific functions
Surrounding the Cell
are the following organelles:
Cell Membrane
• Outer membrane of
the cell
• Double layer
•
• Function: controls
movement in and out
of the cell
Cell Wall
• Most commonly found
in plant cells &
bacteria
• Function: supports &
protects cells
Inside the Cell
are the following organelles:
Nucleus
• Large, round sphere
inside of the cell
• Separated from
cytoplasm by nuclear
membrane
• Function: Directs cell
activities
• Contains chromosomes
(DNA)
Nuclear Membrane
• Surrounds nucleus
• Made of two layers
• Function: openings
allow material to enter
and leave nucleus
Chromosomes
• In nucleus
• Made of DNA
• Function: contain
instructions for traits
& characteristics
Nucleolus
• Inside nucleus
• Function: makes
ribosomes
Cytoplasm
• Gel-like mixture (mostly water)
• Surrounded by cell membrane
Endoplasmic Reticulum
• Function: moves
materials around the
inside of the cell
• Two types:
• Smooth: no ribosomes
• Rough(pictured):
ribosomes embedded in
surface
Ribosomes
• Each cell contains
thousands
• Function: make
proteins
• Found on the rough
endoplasmic
reticulum & floating
throughout the cell
Mitochondria
• Function: produce energy
through chemical
reactions – breaking
down fats &
carbohydrates
• Function: site of cellular
respiration
• Double membrane with
folds on the inside
Golgi Body (Apparatus)
• Function: protein
"packaging plant"
• Function: move
materials out of the
cell
Lysosome
• Membrane bound sac
that contains digestive
enzymes
• Function: breaks down
waste products and
transports undigested
material to cell membrane
for removal
• Cell breaks down
Vacuoles
• Membrane-bound
sacs
• Contains water/other
molecules
• Function: storage and
waste removal
• Function: help plants
Chloroplast
• Usually found in plant
cells (never in animal
cells)
• Contains green
chlorophyll
• Function: where
photosynthesis takes
place