Transcript Cell Structure & Function

http://koning.ecsu.ctstateu.edu/cell/cell.html

A cell is the smallest unit
that is capable of
performing life functions.
Amoeba Proteus
Plant Stem
Bacteria
Red Blood Cell
Nerve Cell
•Prokaryotic
•Eukaryotic

Simplest type of cell

No nucleus or
membrane-bound
organelles

One-celled organisms
(unicellular); bacteria

Bacteria have a
single, circular
chromosome
http://library.thinkquest.org/C004535/prokaryotic_cells.html

Center contains the
DNA

Surrounded by cell
membrane and cell
wall

Contains ribosomes
(no membrane) in
the cytoplasm to
make proteins
http://library.thinkquest.org/C004535/prokaryotic_cells.html




Contain organelles surrounded by membranes (including
a nucleus)
Most living organisms (protists, fungi, plants, and animals)
Some are unicellular, but most are multicellular
Most complex type of cell
Plant
http://library.thinkquest.org/C004535/eukaryotic_cells.html
Animal

Contains 3 basic cell structures
 Nucleus
 Cell membrane
 Cytoplasm with membrane-bound organelles
Plant
http://library.thinkquest.org/C004535/eukaryotic_cells.html
Animal
http://waynesword.palomar.edu/images/plant3.gif
Organelles

Found in bacteria,
fungus, and plant
cells only! (NOT
animal cells)

Made of cellulose

Supports & protects
cells

Found outside the
cell membrane
Outside
of cell

Composed of a double
layer of phospholipids
and proteins

Surrounds ALL cells

Outer membrane if
there is no cell wall

Controls movement in
and out of the cell
(semi-permeable)
Proteins
Cell
membrane
Inside
of cell
Protein
(cytoplasm) channel
http://library.thinkquest.org/12413/structures.html
Lipid bilayer

Gel-like mixture where
the organelles are
found (it is in ALL cells)

80% water

Surrounded by the cell
membrane

Protects cell
organelles

Surrounds nucleus
of eukaryotic cells

Made of two layers

Openings (pores)
allow material to
enter and leave
nucleus

Directs cell activities
in eukaryotic cells
(“control center”)

Contains genetic
material (DNA)
http://library.thinkquest.org/12413/structures.html

“Powerhouse” of the
cell

Found in ALL
eukaryotic cells

Produces energy
(ATP) for the cell
through cellular
respiration by breaking
down fats &
carbohydrates

Makes proteins

Each cell contains
thousands. Found in
ALL cell types

Found on rough ER
& also floating
throughout the cytoplasm.
http://library.thinkquest.org/12413/structures.html

Site of protein synthesis
(made by the ribosomes
on the ER surface)

Rough = ribosomes

Sends proteins and other
materials through the
interior of the rough ER
to the Golgi Body.

Has no surface ribosomes
(smooth)

Makes steroids and ions, &
destroys toxins/poisons

Sends protein, steroids,
ions, and other materials to
the Golgi Body to be USED
in the cell
http://library.thinkquest.org/12413/structures.html

Found in eukaryotic
cells

Modifies, sorts, &
packages molecules
from ER for storage
OR transport out of the
cell

Distributes materials to
other parts of the cell
via vesicles (sacs).

Merges with vacuoles to
digest unwanted materials
and transports them to the
cell membrane for removal.

Contains digestive enzymes
to break down old cell parts

Cell breaks down if
lysosome
explodes (“suicide sac”)

Sac containing
water that helps
maintain the
shape of the cell.

Stores water,
food/nutrients and
wastes
http://library.thinkquest.org/12413/structures.html

Plant cells have a
LARGE central
vacuole
 Needed to regulate
turgor pressure
 Allows the plant to
remain rigid (stiff)
 Without enough
water, the plant will
wilt (droop)
http://library.thinkquest.org/12413/structures.html
Vacuole
Chloroplasts
inside the
cells

Found ONLY in plant cells

Produces a green
pigment called chlorophyll
which absorbs light
energy

Site of photosynthesis,
which uses the energy
from the sun to produce
food (sugar) for the cell
along with oxygen
Plant versus animal
cells

Both have a cell membrane surrounding the
cell

Both have a nucleus

Both contain mitochondria

Animal Cells

Plant cells
 No cell wall
 Cell wall
 Usually round shape
 Usually rectangular
 Nucleus towards center
 Nucleus near cell wall
 Many smaller vacuoles
 Large central vacuole
 No chloroplasts
 Chloroplasts
Is this a plant cell or animal cell?
How can you tell?
32
Contains
organelles; a large
vacuole, a cell wall
and chloroplasts!
Cell Wall
Vacuole
Chloroplast
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Is this a Prokaryotic or Eukaryotic cell?
How can you tell?
34
Contains
organelles; a central
nucleus, and no cell
wall or chloroplasts!
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