Download Organisms release energy stored in food through the process of

Organisms release energy stored in food through the process of cellular respiration
I.
Energy is the capacity or ability to perform ______________________
A. Work is performed when ___________ is moved in a direction it would not move
if left alone
1. Energy makes ___________ possible
2. All organisms require ____________ to stay alive and function
3. Examples of biological work:
a. __________________________
b. __________________________
c. ___________________________
d. ____________________________
e. ____________________________
B. Cells get the ___________________ they need to do ____________ from
________________ which was produced in the process of __________________
1. The food we eat is broken down in our ______________________________
a. Proteins are broken down into ______________________________
b. Carbohydrates are broken down into _________________________
c. Lipids are broken down into ________________ and _____________
d. Nucleic acids are broken down into _________________________
2. The food we eat that is broken down travels through our ____________ to the
____________ (referred to as __________________________________)
3. Cells brake down nutrient molecules, in particular ____________________
to release __________________ to make _______________
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II. The two basic forms of energy are _________ energy and _____________ energy
A. ________ energy is energy that is actually doing work, such as pedaling a bicycle
1. Heat or ________ energy is one kind of ______________ energy
a. Energy associated with the ____________ motion of molecules
b. Responsible for _________________ transport
c. _______________ energy cannot be retrieved and put to work
2. Light is another type of _____________________ energy
B. ______________ energy is the energy that is stored due to an objects location or
arrangement
1. A cyclist motionless at the top of a hill has __________ energy due to
location
2. ________________ in atoms have ______________ energy due to their
position in electron shells
3. Molecules in cells have potential energy due to the arrangement of their
______________; called ________________________ energy
C. Chemical energy is the _________________________ energy of molecules
1. Most important type of __________________ for living organisms
2. ___________________ compounds have structures that make them
especially rich in _______________ energy.
3. The rearrangement of atoms during chemical reactions releases the
_______________ energy
4. This released energy is now available for ___________, such as
contracting a muscle
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III. Two laws govern energy conversions
A. Life depends on the fact that energy can be ____________ from one form
to another.
B. Thermodynamics is the study of energy ______________________
C. First law of thermodynamics states that energy cannot be
_______________ or destroyed, only transferred or __________________
D. The second law of thermodynamics states that energy conversions reduce
the _______________ of the universe.
1. During every energy transformation, some energy becomes
___________ energy, unable to do ____________________
2. In most energy transformations, most usable forms of energy are
at least partly ______________________ to heat
3. Heat , which is random molecular motion, is one form of
__________________
4. In the process of carrying out chemical reactions that perform
various kinds of work, living cells unavoidably ______________
organized forms of energy to ____________________.
5. _______________ is the amount of disorder
6. Because of the second law of thermodynamics, a cell cannot
transfer or transform energy with ________________ efficiency
7. Some energy always ___________________ the system as heat
8. Cells do not have the machinery to put the disordered
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molecular movement of ________ energy to work except to
___________ the body.
9. Thus energy cannot be _________________________
IV. Life’s chemical reactions either store or release energy
A. Endergonic reactions require a net _________________ of energy
1. Yield products that are rich in ____________________ energy
2. Energy is _______________ from the surroundings as the
reaction occurs
3. Energy is stored in the _____________ bonds of the products
4. Photosynthesis is an _________________ reaction and anabolic
a. Energy is ____________________
b. Builds _________________ molecule from _______________
molecules
B. Exergonic reactions _______________ energy
1. ______________ bonds of reactants contain more energy than
those in the _________________
2. Cellular respiration is an _______________ process and
catabolic
a. ____________________ energy
b. breaks down ______________ molecule into ______________
molecules
V. ATP provides energy for cellular work
A. The amount of energy in a single glucose molecule is way _______________
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For a single ____________________________ in a cell.
B. In fact if all the energy of a ________________ molecule were
_________________ at once inside a ___________, it would _____________
the ________________
C. Thus the cell breaks down ___________________ bit by bit and distributes
little packets of energy to molecules called ______________
D. _______________ stands for adenosine triphosphate
1. Adenosine part consists of
a. ____________ containing base called ____________________
b. ___________ carbon sugar called _________________
2. The triphosphate consists of three _______________ groups
a. Source of energy used for most cellular ______________
b. Phosphate groups are __________________ charged
c. Since like charges ____________, the crowding of three
____________ charged phosphate groups contributes to the
___________________ energy
d. Analogous to a _________________ spring
e. When a phosphate group is broken off ____________ energy
is released
f. Resulting molecule is adenosine diphosphate (___________)
E. During a chemical reaction that breaks one of ATP’s bonds, the phosphate
group is transferred from ____________ to another __________________
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F. The molecule that accepts the phosphate group undergoes a
_____________, driving the __________________.
G. Cells perform three main types of work
1. _______________________ work
a. ________________________ of a muscle
b. ATP __________________ phosphate to certain protein
c. Protein _______________ shape leading to muscle contraction
2. _________________________ work
a. Building a _______________________ such as protein
b. ATP provides energy for the process of __________________
that links amino acids together
3. _______________________ work
a. Pumping solutes such as ions across a membrane
(_____________________________________)
b. Transport protein receives ________________ from ATP,
___________ shape and thus allowing ions to pass through
membrane
H. ATP is continually recycled, going from _______ to _________ and back
VI. Breathing supplies oxygen to our cells and removes carbon dioxide
A. Cellular respiration is an aerobic process, meaning that it requires
_______________
1. Breathing is also called ________________ but is different than
cell respiration
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a. Breathing is taking ______________ into our lungs which will
be distributed by ___________________________ to our cells
b. The cells will use that ____________ for cellular respiration
c. Breathing also disposes of ______________________ from
our ___________________ to the outside environment
d. Carbon dioxide is a waste product of _________ respiration,
which leaves the cell by ______________ and is carried by
______________________ to lungs.
VII. Review structure of mitochondria
VIII. Cellular respiration converts energy stored in _____________ to energy in
_____________
A. In cell respiration, a complex molecule (__________________) is broken
down into smaller molecules that have less ________________ energy than
the original substance.
1. Organic compounds such as ____________ react with
__________
2. Produce ______________________ and water as waste products
3. Produce about _______ molecules of ______ per sugar molecule
B. Cellular respiration converts about _______ percent of the energy from
food into _____________ energy
1. 60% of the energy is converted to _____________ energy, which
is lost from the body in the form of __________________
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a. Thus cell respiration allows us to maintain a constant
temperature, even in a __________ environment.
b. When we exercise, cells increase their rate of
_____________________, thus we feel _______ after exercise
c. Excess heat is lost through ________________________
2. Instead of releasing energy all at once in a burst of flame, cellular
respiration unlocks the energy in glucose in _________ amounts by
breaking down _____________ in ______________ steps.
C. In cell respiration high ______________ electrons are pulled out of
glucose in several steps and passed down an _____________ transport
chain
1. As electrons undergo each transfer in the chain, they release a
little _________________.
2. In a process known as _____________________, the released
energy is trapped and used to make ______________.
3. The final molecule in the chain to accept electrons is _________
4. Thus electrons move from _______ to __________ during cell
respiration
D. The general equation for cell respiration is
_____________________________________________________________
IX. Cellular respiration occurs in three main stages
A. _____________________ is the first stage, takes place outside the
____________________ in the cytoplasm, and requires no ____________
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1. Initiates the breakdown of ____________ into two three carbon
molecules called ________________ in a 9 step process
a. This requires two molecules of _______ energy to get started
b. As the reactions occur two intermediate three carbon molecules
transfer electrons and hydrogen ions to an electron carrier
molecule ________________________
*This converts NAD+ to ______________________
*NAD+ is similar to ______________ in photosynthesis
* they are both electron carriers that shuttle ______ energy
electrons
c. In addition, four new _________ molecules are produced, a net
gain of ____________ molecules
2. _____________ is the universal energy-harvesting process of life
a. Because Glycolysis occurs universally, it is thought to be an
________________________ metabolic system
b. Glycolysis today is probably very similar to the process the
___________ cells on Earth used to extract energy from their
environment
3. In summary, the original _________ molecule has been
converted into two molecules of _____________ and two
_______ molecules were spent, Four ___________ molecules
produced, and two __________ molecules with high energy
electrons formed
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4. The pyruvic acid molecules still hold most of the ___________
of the original glucose molecule.
B. The Kreb Cycle is the second stage, takes place within the mitochondrial
____________ and completes the breakdown of _____________ to carbon
dioxide
1. Pyruvic acid, the end product of ______________________ does
not itself enter the Kreb cycle
a. Two pyruvic acid molecules diffuse through the mitochondrial
membrane into the ____________________
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b. Each three carbon _______________________ molecule loses
a carbon dioxide molecule
c. The resulting molecule is converted into a two carbon molecule
called ___________________________
d. Two acetyl CoA molecules enter the ________________ for
each glucose molecule
e. In the process of going from pyruvic acid to acetyl CoA
________________ and hydrogen ions are transferred to
NAD+
f. Thus two more ________________ molecules are formed
2. For each acetyl CoA that enters the Kreb cycle
a. _________________ ATP molecule is made
b. _______________ NADH molecules are formed
c. ______________________ FADH2 molecule formed
d. ____________________ carbon dioxide molecules
3. Thus for one glucose molecule
a. Two _________________ are made in Kreb cycle
b. Six ___________________ molecules are made in Kreb cycle
c. Two ________________________ are made in Kreb cycle
d. Four ________________________ are made in Kreb cycle
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C. Electron transport chain is the third stage, takes place in ___________, and
obtains _________________ from NADH and FADH2 to pass down chain
and form ______________ by chemiosmosis
1. ______________ and FADH2 transfer ______________ obtained
from original glucose molecule during glycolysis and Kreb cycle to
the _______________________________________ chain
2. NAD+ and _______________ are ________________________
3. As electrons move from molecule to molecule in chain some
_______________ is released
4. This energy is used to pump _________________ ions across
________________ into intermembrane space (opposite of
________________________________)
5. This creates an ________________________________ gradient
which store _____________________________ energy
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6. Hydrogen ions rush back through the protein ATP
______________________ in the cristae.
7. ATP synthase uses the energy from the flow of
_____________________ ions to convert ADP to __________
8.
Up to _________ ATP molecules are generated from one
glucose molecule
9. The final electron acceptor in chain is _______________ which
takes electrons and hydrogen ions to form ________________
X. The result of cell respiration is to generate ATP for cellular work
A. A cell can convert the energy of one glucose molecule to as many as
______ molecules of ATP
1. Glycolysis produces ________ ATP’s
a. However, it requires _________ ATP’s to get started
b. Net gain of ______________ ATP molecules
2. Kreb cycle produces _________ more ATP molecules
3. ATP synthase produces about ________ ATP molecules
4. Notice that most ATP production requires ____________
XI. Fermentation is an anaerobic alternative to aerobic respiration
A. Fermentation makes ATP without using _______________ by depending
solely on _______________
B. When yeast cells are placed in an anaerobic environment (without
_____________) where there is plenty of glucose they can thrive by using
_________________________ only
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C. The problem with using glycolysis as the sole means of producing ATP is
that _____________ gets depleted. There is no electron transport chain to
recycle it back.
D. Yeast solve this problem by a process called ________________
fermentation
1. Pyruvic acid produced by ______________ is converted into
alcohol and carbon dioxide
2. In the process NADH is converted back to _______________
3. Thus alcoholic fermentation replenishes ___________ to continue
glycolysis
4. Alcohol still contains plenty of chemical energy which is not used
5. Alcoholic fermentation is used to make alcohol and bake bread
E. When a person sprints their lungs and blood stream can’t supply
____________ fast enough to meet muscles need for energy
1. Muscle cells can use an _____________ process called
___________________________________fermentation
2. Pyruvic acid produced by ________________ is converted into
lactic acid
3. In the process NADH is converted back to ________________
4. Lactic acid also contains untapped _________________ energy
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