Name _________________________ Section _____________ Date_______________
Cellular Respiration
During photosynthesis, plants
produce glucose. Why do
plants need glucose? _______
_________________________
_________________________
Do plants have mitochondria?
Do animals have mitochondria?
Why do they need
mitochondria?
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

From: www.micro.magnet.fsu.edu/.../ mitochondria.html
Cellular Respiration’s 3 Main Stages
Reactants
Products
(include # of
ATP)
Glycolysis
Mitochondria - ___________
_______________________
_______________________
Inner mitochondria
membrane - _____________
_______________________
_______________________
Matrix - ________________
_______________________
_______________________
_______________________
Net ATP
Produced
Location of
Reactions in
Cell
In cytoplasm
of the cell
Krebs Cycle
In matrix of
mitochondria
Electron Transport
Chain
On inner
membrane of
mitochondria
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Name _________________________ Section _____________ Date_______________
Cellular respiration is the process by which cells harvest stored potential energy in
__________ and transfer it into stored chemical energy in _______. ATP is a molecule
that can easily transfer energy to other molecules during chemical reactions.
Chemical equation for cellular respiration
C6H12O6 + + 6O2 --> 6CO2 + 6H2O + ATP
Examine the structures of the following reactants and
products of this equation.
Chemistry review:
a) How many carbons are
there in C6H12O6? _______
b) How many oxygen
molecules are reactants in
this equation? __________
a. What are the names of these three molecules?
b. Which molecule has the most covalent bonds?
c. These are all covalent bonds. In covalent bonds __________________ are shared.
d. It takes energy to hold atoms in one place rather than let them move independently.
Considering this piece of information, which of the three molecules above stores more
energy? Explain your answer.
Redox Reactions
Chemical reactions that involve the movement of electrons from one molecule to
another are called redox reactions. Electrons leave a molecule only when it comes into
contact with another molecule that attracts it more strongly.
Oxidation: when a molecule ________ an electron
Reduction: when a molecule _________ an electron
When electrons are attracted to a molecule, the negative charge of the electron usually
attracts a proton (H+) from the surrounding cellular fluid. (There are always protons
around because water always contains some protons.)
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Name _________________________ Section _____________ Date_______________
Glycolysis – Oxidize glucose to make pyruvic acid
1. ______________ split into G3P (Uses ATP)
2. Through a series of ____________________,
G3P is oxidized into ________________________.
Energy released is transferred to ________ and
________.
Images from http://www.emc.maricopa.edu/faculty/farabee/BIOBK/enyld1.gif
and http://www.uic.edu/classes/bios/bios100/summer2005/conversiona.jpg
Pyruvic acid groomed to produce Acetyl CoA
needed for Krebs Cycle
1. NAD+ is ________________ and pyruvic acid is _______________.
2. A carbon atom is removed, bonds with ____________ to form carbon dioxide
(______) and is released.
3. Coenzyme A, derivded from a B vitamin, joins ________________ to become a
different molecule called acetyl coenzyme A.
Krebs Cycle – Energy in Acetyl CoA transferred to ATP and electron carriers
1. ___________________ binds
with a 4-carbon molecule, forming a
6-carbon molecule (citric acid.)
2. Through a series of ___________
___________________, energy is
transferred from citric acid to ATP,
NADH, and FADH2.
3. The energy in ATP can be used
directly by the cell. The energy
stored in NADH and FADH2 can be
converted to ATP by the electron
transport chain.
http://www.sp.uconn.edu/~bi107vc/images/mol/krebs_cycle.gif
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Name _________________________ Section _____________ Date_______________
Electron Transport Chain & Chemiosmosis: Cashing in the electrons to make ATP
1. _________ and ________ pass electrons to an electron transport chain.
__________________ is the final molecule in the electron transport chain. The oxygen
balances the negative charge of the two electrons it accepts by taking two _________
from its surroundings. Thus, it forms _____________.
2. Energy from the _____________________ of the electron transport chain is used
pump __________ across the membrane.
3. H+ move through _______________ from areas of high concentration in the
intermembrane space into areas of low concentration in the mitochondrial matrix. This
______________, ATP synthase, uses the energy created by the concentration
gradient to make __________. This process is called __________________________.
Image source: www.sirinet.net/~jgjohnso/ respiration.html
Key Terms to Know
cellular respiration
Aerobic
Anaerobic
Chemiosmosis
Oxidation
Reduction
Redox reaction
Glycolysis
Krebs Cycle
Alcoholic fermentation
Lactic Acid fermentation
Mitochondrion (pl. –dria)
Pyruvic acid
Acetyl Coenzyme A (Acetyl CoA)
NAD+/NADH
FAD/FADH2
ATP
Electron transport chain
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Name _________________________ Section _____________ Date_______________
Total Maximum Yield of ATP from Cellular Respiration
2 ATP from Glycolysis
2 ATP from Krebs Cycle
34 from Electron Transport Chain
38 ATP per 1 Glucose molecule
Source:
www.sirinet.net/~jgjohnso/
respiration.html
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Name _________________________ Section _____________ Date_______________
Fermentation – What to do when you are without O2 ?
Without oxygen present to ___________________, there can be no electron transport
and no high yield of ATP. But anaerobic respiration (fermentation) provides some ATP
using glycolysis. There are two fermentation pathways.
Alcoholic Fermentation
Ex. – yeast- and bacteria-produced alcohols
Steps to Fermentation
1. ______________ used
to make _________ from
glucose and form pyruvic
acid.
2. ____________ reacts
with NADH to form ethanol
(__________ fermentation)
or lactic acid (__________
fermentation).
www.emc.maricopa.edu/.../ BIOBK/BioBookGlyc.html
Lactic Acid Fermentation
Ex. – human muscle, yogurt
Key to fermentation is
that NADH is recycled so
_____________ can
From:
continue to occur and
___________ can form.
Without recycling NADH,
the cell would stop making
ATP and die! Ethanol and
lactic acid are not the goal
of fermentation. They are
simply by-products of the
process.
Fermentation yield:
2 ATP from each glucose
How does this yield
compare to that of aerobic
respiration?
______________________
From: www.emc.maricopa.edu/.../ BIOBK/BioBookGlyc.html
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