Cell Physiology

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Cell Physiology
How do cells FUNCTION (work)? STERNGRR Processes
take place at the cellular level!

• Cell Transport
• Photosynthesis
• Cell Respiration

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Cell Transport
Cell Transport is a STERNGRR process Lets food
in for NUTRITION Lets oxygen in for
RESPIRATION Lets waste out for EXCRETION
Materials move in/out of cells through the cell
membrane
The cell membrane is SELECTIVELY PERMEABLE
Phospholipid bilayer
Membrane protein
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Types of Cell Transport
Passive Cell Transport Active cell transport
Does NOT require energy Requires energy
Movement DOWN the concentration gradient Movement AGAINST the concentration gradient
High ? Low Low ? High
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Diffusion
Diffusion is a type of Passive Transport Lets
food in for NUTRITION Lets oxygen in for
RESPIRATION Lets waste out for EXCRETION
Movement of molecules from a high to low
concentration
Example Oxygen is moved from a high
concentration in the lungs, to a low
concentration in the blood
Molecules move until they reach EQUILIBRIUM An
equal concentration on both sides of the membrane
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Osmosis
Osmosis is a type of diffusion (a type of
passive transport)
Movement of WATER molecules from a high to low
concentration
Example In salt water, there is more WATER in
the cell than in the surrounding environment, so
water leaves the cells and they shrivel
Molecules move until they reach EQUILIBRIUM An
equal concentration on both sides of the membrane
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Cell Energy
Cell Energy Processes include Photosynthesis
and Cellular Respiration
Photosynthesis is a STERNGRR process
Cellular Respiration is a STERNGRR process
The two processes work together in a cycle!
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Photosynthesis
Involves making FOOD (sugar/glucose) for
nutrition CO2 H2O sun ? C6H12O6 O2
REACTANTS PRODUCTS Occurs
in the CHLOROPLASTS of plant cells. Uses the
green pigment CHLOROPHYLL to capture light
energy Green light is reflected all other
wavelengths of light are absorbed by the
plant.
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Photosynthesis
What is going in and coming out of the plant?
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ATP
The food made in photosynthesis is used to make
energy for cells! Food is NOT energy! They are
2 different things!
Organisms (including plants) must use this food
to produce energy
Plants make food for all living organisms (sugar)
ATP is the energy molecule for cells
Adenosine
P
P
P
Energy is stored in a chemical bond when the
bond is broken, energy is released!
Energy
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Cellular Respiration
Involves using food made in photosynthesis for
respiration, to make ATP for energy. C6H12O6
O2 ? CO2 H2O ATP REACTANTS
PRODUCTS Occurs in the Mitochondria of ALL
cells

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Cellular Respiration
Cellular respiration can take place WITH Or
WITHOUT Oxygen!
Anaerobic respiration (fermentation) takes place
when oxygen is NOT present
Aerobic respiration occurs when oxygen is present
Makes a LOT of ATP
Makes a little ATP
In plants and microorganisms Alcoholic
fermentation
In animals Lactic acid fermentation