Download CellularRespirationReview

Define Cellular Respiration.
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The process in which biomolecules, like
sugar, are converted into an energy
form that living things can use (ATP).
How many types of Cellular
Respiration are there?
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Two Types: Aerobic or Anaerobic
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Distinguish between these.
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With or without oxygen
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How much ATP does each yield?
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Aerobic yields 36 or 38 ATP
Anaerobic yields only 2, but gives NAD
back to glycolysis to keep the process
going.
What do cells do with the energy
they get from food?
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Store it as ATP or
Release as heat
Chemical Equations
Photosynthesis: light energy converted to
chemical energy
 CO2 + H2O =
O2 + glucose
Cellular Respiration: biomolecules
converted to ATP
 O2 + glucose = CO2 + ATP
Where is the energy stored in biomolecules like
sugars, carbs, lipids, etc.?
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In the bonds between the atoms
Where in the bonds is energy
stored in ATP?
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In the bond between the second and
third phosphate
How do living things access and convert the
energy stored in biomolecules?
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Break existing bonds and form new
ones
What is the name for the series of reactions
that converts the stored energy in biomolecules
into molecules of ATP?
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Cellular Respiration
What is the first stage of cellular respiration called?
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Glycolysis
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Where does this step occur?
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In the Cytoplasm
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Is this aerobic or anaerobic?
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Anaerobic
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What are the products of this step?
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ATP, NADH, and 2 3-C Pyruvate molecules
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What is the net production of ATP in this step?
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2 ATP’s
If oxygen is available where
do the pyruvates go?
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To the Mitochondria
What type of Cellular Respiration is
this?
Aerobic
What happens in the Prep
Step?
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The pyruvates are transported into the
mitochondria.
They lose a carbon (CO2 given off)
2 carbon acetates are formed—they use
NAD and Co enzyme A to become…
acetyl Co A
Diagram and describe the events of the prep step
(pyruvate conversion)
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2 3-C pyruvate molecules are
converted to…
2 2-C acetate molecules with the
production of…
2 molecules of NADH and 2 molecules
of CO2
Diagram the events of the Kreb’s Cycle indicating the
number of NADH, FADH2, ATP, and CO2 molecules
produced
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The Krebs Cycle produces electron
carriers a CO2 is released leaving…
6 NADH, 2 FADH2, 2 ATP, 4 CO2
What is the significance of the four CO2 molecules
produced in the Kreb’s Cycle?
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The four carbons in the four CO2
molecules plus the two carbons in the
two CO2 molecules from the prep step
are evidence that the initial six carbon
sugar molecule is completely broken
down
Describe what the electron transport chain is and where
it is located in the mitochondria.
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The ECT is a series of protein molecules
embedded on the inner membrane of
the mitochondria that each have a
higher attraction for electrons than the
previous one.
What is the source of electrons to the electron transport
chain?
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The co-enzymes NADH and FADH2
Every time an electron is accepted and released by a protein in the
electron transport chain –
a redox reaction releases a small amount of energy used to do
what?
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Actively transport a H+ ion from the
matrix into the outer compartment
What happens when a
molecule is reduced?
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It accepts electrons.
What happens when a molecule is
oxidized?
It loses electrons.
What is this reaction called?
A Redox Reaction.
Mnemonic Strategy
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LEO the lion says GER
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Lose Electrons=Oxidize
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Gain Electrons=Reduce
Where do H+ ions become highly concentrated?
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In the Outer compartment
Are these ions freely permeable to the
membrane?
No, so…how can they diffuse through
the membrane into the outer
compartment?
Through ATP Synthetase transport
proteins.
Is the diffusion of H+ ions energy releasing or energy
requiring?
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Releasing
Is the formation of ATP from ADP
energy releasing or energy requiring?
Requiring
Link these two statements in explaining
the formation of ATP.
The energy released in the diffusion of
H+ is required to form ATP.
How many ATP molecules can be created from the
electrons delivered by NADH?
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3/NADH
How many ATP molecules can be created
from the electrons delivered by FADH2?
2/FADH2
What serves as the final electron acceptor in
aerobic respiration?
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Oxygen
What happens to pyruvates if oxygen is not
available?
Pyruvates stay in the cytoplasm and
participate in Lactic Acid Fermentation
pathways.
Diagram the lactic acid anaerobic respiration pathway
that occurs in animals
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2 3-C Pyruvates-->2 3-C Lactic Acid
2 NAD+ molecules are produced in this
step
What products from lactic acid
fermentation are re-cycled in the
respiration pathways?
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NAD+ to re-start glycolysis
How many ATP molecules per glucose are
formed in lactic acid fermentation?
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2 ATP’s/glucose
What kind of fermentation do
yeasts and bacteria undergo?
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Alcoholic fermentation
Why do you “feel the burn” when
you are exercising strenuously?
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Lactic acid fermentation
There is a build up of lactic acid in the
muscles due to anaerobic lactic acid
fermentation.
Give two reasons why muscles
can’t contract well when fatigued
during strenuous exercise.
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1. Only get 2 ATP per glucose due to
anaerobic respiration.
2. Lactic acid molecules build up in
muscles and interfere with muscle
contractions.
Why is it valuable that animals
can respire anaerobically?
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It allows animals to exert energy at a
high intensity for a short period of
time– times of stress for fighting or
fleeing.
If we were not able to do anaerobic
respiration, we would pass out when we
had a decrease of oxygen
Compare: Photosynthesis and
Cellular Respiration
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Location: Where does each take place?
Photosynthesis happens on the
thylakoid membrane.
Cellular respiration happens on the
inner membrane of the mitochondria.
Both build up a concentration of
hydrogen to power the transformation
of ADP into ATP.
Compare -- Photosynthesis vs.
Cellular respiration
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Source of electrons:
Photosynthesis gets electrons from—
breakdown of water molecules (photolysis).
Cellular respiration gets electrons from—
FADH2 and NADH from Krebs cycle.
Final electron acceptors= NADP+ in
photosynthesis and Oxygen in aerobic
respiration.
Cycles
Photosynthesis has Calvin cycle….
adds carbon to make sugar.
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Cellular Respiration has the….
Krebs cycle--creates source of electrons
and ATP for larger production of ATP
Compare--- Organisms that do
photosynthesis and cellular
respiration.
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Photosynthesis happens …
only in plants.
Cellular respiration in both plants and
animals.
Review
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Cellular respiration –Two basic stages:
Glycolysis and Krebs Cycle
Glycolysis yields 2 ATP
Aerobic respiration (Krebs and ECT) yields:
36 0r 38 ATP
If no oxygen is available..
Fermentation begins and NAD+ is recycled back into..
Glycolysis which continues until…
Oxygen is available.
Review
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Two kinds of fermentation:
Alcoholic and Lactic Acid
Alcoholic fermentation is done by:
Yeast, bacteria, fungus and creates foods like
Beer, wine, cheese, bread
Lactic acid fermentation happens in
animals and some fungi. It causes..
Sore muscles after anaerobic exercise.
The End
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Good Luck!