Transcript Cells

Cells
Theory, Structure, Function
What is a Cell?
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The smallest unit
that can carry on all
the processes of life
Robert Hooke
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1665 Cork Cells
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“A lot of little boxes”
Dead Cells
Anton van Leeuwenhoek
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1673
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Hand lens
First live cells
Schleiden
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1838
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observed that plants
are composed of
cells
Schwann
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1839
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observed that all
animals are
composed of cells
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Yes humans are
animals
Virchow
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1858
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observed that cells
come from other
cells (reproduction)
Cell Theory
1. All living things are made of one or
more cells.
 2. The basic unit of structure and
function within an organism is the cell.
 3. All cells arise from existing cells.
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Create a Timeline
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Must include:
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Accurate time increments
4 Pictures
Descriptions of each scientist
accomplishment
Schleiden
 Hooke
 Van Leeuwenhoek
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Schwann
Virchow
What is a Prokaryote?
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An organism that
lacks a nucleus
Lacks other
membrane bound
organelles
Ex. Bacteria
What is a eukaryote?
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Organism that has a well defined nucleus
Contains membrane-bound organelles
Some Specialized cells can function
without a nucleus, Ex. Red blood cells
Ex. Plants, Fungi, Animals, Humans
Create a T-Chart
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With your shoulder partner create a Tchart that state the Differences
between Prokaryotes and Eukaryotes.
Prokaryotes
Eukaryotes
1.
2.
3.
1.
2.
3.
What are the two types of
organisms?
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Unicellular – a complete living organism
that consists of only one cell
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Examples – bacteria
Multicellular – a living organism
consisting of more then one cell
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Examples – animals, plants
Level of Organization
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Cell  tissue  Organ  Organs
system  Organism
What is an organelle?
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A cell component that performs specific
functions
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Example – nucleus, cell membrane
Cell Membrane
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The outer boundary
of the cell
Gives shape and
flexibility to the cell
Is semi-permeable
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Security guard
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Mitochondria
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Breaks down food
molecules and
releases energy in
the form of ATP
Battery/Generator
Chloroplast
Only found in Plants
 Green
 Site of Photosynthesis
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Golgi Apparatus
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Receives proteins from
ER and chemically
modifies them
Processes, packages,
and secretes cell
products
Uses vesicles for
transport
UPS
Ribosomes
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The site of protein
synthesis
Can be attached to
the ER or float loose
in the cell
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Line workers
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Endoplasmic Reticulum (ER)
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Rough ER with
ribosomes
Smooth ER w/out
ribosomes
Prepares proteins for
export
breaks down toxic
substances;
Can be rough or
smooth
Lysosome
Contains digestive
enzymes
 Digests and rids the
cell of waste
 Prevents bacteria
and viruses from
invading
 Performs:
Program Cell Death
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Nucleus
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The cells brain
Contains
chromosomes (DNA)
Involved in protein
synthesis
Boss/Manager
Nucleolus
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The nucleolus is
within the nucleus.
ribosome RNA are
synthesized
Cell Wall
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Only in plant cells
Thicker then the
membrane
Relatively inflexible
Protects and
supports the cell
Block wall
Cytoplasm
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Semi-fluid material
inside a cell
Nutrient rich
Major cell organelles
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Cilia and Flagella
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Hair-like organelles that extend beyond the
surface of the cell
Assist in movement
Vacuole
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Sack of fluid surrounded
by a membrane
Stores food, enzymes or
waste.
Animals cells typically
have many small ones
Plant cells typically have
one large one
Storage closet
Plant cell vs. Animal cell
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Plant Cells have:
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Cell Wall
One Large vacuole
Plastids (stores food or pigment which give
color to plant)
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Chloroplast
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Solar panel
Closing Quiz
1.
2.
3.
4.
Cells
Which organelle propels a cell through an
environment? Hint there are two possible
answers.(1 pt)
Which organelle is the final processing
center for a protein? (1pt)
Which three organelles are present in plant
cells but not animal cells? (3 pts)
What is the difference between a
prokaryote and a eukaryote? (1 pt)