Transcript cells.

Ch. 7 Notes
History of Cells
Robert Hooke
(1665).
 Observed “cork.”
Said “cork was
made of little
compartments that
looked like monk’s
“cells.”
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Modern Cell Theory
Cell Theory:
 ***Cells are the smallest
working units of life.
 ***All living things are
made of cells.
 ***All cells come from
pre-existing cells.
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Cell Factory
The cell is like a
factory.
 People and
machines perform
functions in a
factory.
 There are parts of a
cell that also
perform different
functions.
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Cell Factory
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All factories produce a
product.
CELL PRODUCT=PROTEINS
 Cell’s DNA codes for
proteins!
 All cells in an organism
have the same DNA, but
different cell types produce
different proteins.
 What is needed to build a
protein?
Parts of All Cells
Cytoplasm- watery
substance inside all
cells.
 Consists of water and
anything in it.
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Parts of All Cells
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ALL CELLS HAVE A CELL
MEMBRANE
Cell membrane- “door” to the
factory that’s made of lipids
and proteins.
Also known as the
phospholipid bilayer.
Semi-permeable-only certain
things pass through.
Aids in homeostasis—stable
internal conditions
Phospholipid Structure
Phospholipid Structure
Hydrophilic = “water loving”
 Hydrophobic = “water hating”
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Parts of All Cells
Receptor proteins- allow cells to talk to
one another.
 Cells send “messages” and others
receive them with receptors.
 Hormones-cellular messages
Ex.) Testosterone
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Parts of All Cells
Marker proteins -gives
your cells an “identity.”
 Distinguishes your
cells from other cells.
– Blood and tissue
types
– Immune system

A marker
A and B
markers
B marker
No marker
Parts of All Cells
Channel proteins allow molecules to
pass through the
membrane.
 Selective about what
passes through.
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Parts of All Cells
Ribosomes -“assembly line
workers.”
 They build proteins.
 Found all over cell
 Once built, proteins are
either used by cell or
shipped out to other cells.
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Prokaryotic vs. Eukaryotic
Cells
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Bacteria
Small
No organelles
except ribosomes.
No nucleus.
Simple
Anything other than
bacteria, like plants and
animals, have these cells
 Large cells.
 Organelles.
 True nucleus.
 Complex
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Eukaryotic Cells
Organelles - little,
specialized organs
found in all eukaryotic
cells, not prokaryotic.
Eukaryotic Organelles
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Nucleus-“central office” of the cell that
contains DNA where most cell activity is
started
DNA carries instructions for how to build
something. What?
Nucleus is surrounded by a porous
membrane. Why?
Another organelle
the nucleolus, is found
in the nucleus and
makes the ribosomes.
Cell Video —4min
Eukaryotic Organelles
Mitochondria-powerhouse of the cell where
cellular respiration occurs.
 Some cells have more than others—why?
 Contain own DNA
 Supplies cell with energy through cellular
respiration--convert food energy (carbs) to
cellular energy (ATP).
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Eukaryotic Organelles
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Cellular respiration- process that occurs in
mitochondria in which organisms consume
carbohydrates and oxygen, releasing carbon dioxide,
water, and energy for life (ATP).
 C6H12O6 + 6O2 → 6CO2 + 6H2O + energy (ATP)
 This is why we use oxygen and how we use carbs to
get energy!!!
 Plants and animals all respire
 The opposite of photosynthesis!!!
Eukaryotic Organelles
Endoplasmic reticulum -“highway”
system throughout inside of cell.
 Materials can travel on it throughout the
cell.
 Rough ER vs. Smooth ER.
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Eukaryotic Organelles
Golgi apparatus-“packaging center” of
the cell.
 Puts finishing touches on proteins and
prepares them for shipment out of the
cell.
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Eukaryotic Organelles
Lysosome -recycling center.
 Repairs damaged cell parts.
 Sometimes parts are beyond repair.
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Eukaryotic Organelles
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Vacuolesstorerooms in
plant and animal
cells. What would
they store?
 Larger in plant
cells than animal
cells. Why?
 If they shrivel, so
does the cell
Plant vs Animal
Eukaryotic Cells
Cell wall for
structure AND cell
membrane.
 Larger vacuoles.
 Chloroplasts
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Cell membrane only.
 Small vacuoles.
 No chloroplasts.
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Plant vs Animal
Eukaryotic Cells
Plant
Eukaryotic Cells
•Cell wall -surrounds the
plant cell membrane
•Is made of cellulose,
a carb—paper is this.
•Give plant cells support
and structure
•Protect cell from bursting
if vacuole absorbs a lot of
water
Plant
Eukaryotic Cells
Chloroplast-organelle
where photosynthesis
occurs.
 Have DNA like
mitochondria
 Chlorophyll-green
pigment in chloroplasts
that gathers sunlight
needed for this process
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Plant
Eukaryotic Cells
•Chloroplasts found only in
photosynthetic organisms
(plant cells, some bacteria,
and some protists)
•Make energy source
(carbs) from light
Photosynthesis in Plant Cells
Source of energy for ALL life on Earth!!!
Reactants
Products
1. Water
1. Oxygen gas
2. Carbon Dioxide
2. Glucose (a carb)
3. Sunlight
Photosynthesis in Plant Cells
Photosynthesis in Plant Cells
Photosynthesis
Cellular Respiration
Endosymbiotic Theory
Endosymbiotic Theory -mitochondria and
chloroplasts were once prokaryotic cells
that were taken in by other prokaryotes.
 Creation of first eukaryotic “organelles”
 Prokaryotes evolved into eukaryotes
 Endosymbiotic Theory—3min
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