Transcript 1. The smallest living unit is a _____. A. proton B

1. Glucose contains more energy than the products of
its metabolism, CO2 and H2O.
True
___
False
2. All chemicals have the same amount of potential
energy.
True
___
False
3. Organisms require a constant supply of energy
because _____.
A. they cannot create energy
B. when they transform energy some is lost as
heat
C. maintenance of their cellular organization
requires a lot of work
D. all of the above
___
4. Which of the following is an example of potential
energy?
A. a big piece of chocolate cake
___
B. someone running a marathon
C. a fish swimming upstream
D. a leaf unfolding
5. Energy is needed by organisms to
_____________.
A. respond to stimuli
B. reproduce
C. grow
D. all of the above
___
6. The entropy of the universe is decreasing.
True
False
___
7. About ten times as many people can be sustained
on a diet of vegetables and grain as can be sustained
on a diet of meat.
___
True
False
8. Energy that is doing work is _____.
A. called potential energy
B. stored in the bonds of glucose
C. called kinetic energy
___
D. both A and B
9. Which of the following statements about energy is
FALSE?
A. Energy can't be created and it can't be
destroyed.
B. Chemical energy in our food can be
transformed into energy needed for muscle
contractions.
C. When energy is transformed, all of it is
___
available to do work.
D. A battery you just bought at the store has
potential energy.
10. The amount of energy contained in one
population that is taken up by the next population is
about _____.
A. 100%
B. 90%
C. 50%
D. 10%
___
11. Energy is constantly supplied to ecosystems by
_____.
A. radioactive elements
B. the sun
___
C. heat from the ocean's thermal vents
D. gravity
12. The use of fossil fuels by our society has
increased the efficiency of food production.
True
___
False
13. Reactions which require an input of energy
___________.
A. are exergonic
___
B. are endergonic
C. will never occur
14. In the reaction A + B --> C + D, the reactant(s)
is/are ______________.
A. only A
B. A and B
___
C. only D
D. C + D
15. If the change in free energy in both directions of
a reaction is just about zero, the reaction is
reversible.
___
True
False
16. Once ATP breakdown is coupled with muscle
contraction, the overall process becomes exergonic
and muscle contraction
occurs.
___
True
False
17. The breakdown of ATP to ADP + P is a _____
reaction.
A. exergonic
___
B. endergonic
C. coupled
18. Which of the following is an example of an
endergonic reaction?
A. muscle contraction
B. protein synthesis
C. nerve conduction
D. all of the above
___
19. All of the energy in glucose is transformed into
ATP by the mitochondria.
True
___
False
20. The "energy currency" of the cell is _______.
___
A. ATP
B. glucose
C. ADP + P
D. starch
21. ATP is a _____.
A. protein
B. lipid
___
C. nucleotide
D. polysaccharide
22. Active transport could be described as _____.
A. exergonic
B. endergonic
___
23. The nitrogen base in ATP is _____________.
A. guanine
B. thymine
C. uracil
D. adenosine
___
24. When ATP becomes ADP + P, just enough energy
is released to make cilia beat so little energy is
wasted.
___
True
False
25. In a metabolic pathway, reactions occur
haphazardly and have nothing to do with one
another.
True
False
___
26. Enzymes are _____.
A. nucleotides
B. proteins
___
C. lipids
D. monosaccharides
27. Enzymes _____.
A. slow down chemical reactions
B. increase the energy of activation
C. bring together specific molecules and causes
___
them to react with each other
D. all of the above
28. Enzymes lower the energy of activation of
reactions so they can occur at body temperature.
___
True
False
29. In the metabolic pathway below, which letter
does NOT represent a reactant?
A --> B --> C --> D --> E
A. B
B. C
C. D
___
D. E
30. Which of the following is NOT an enzyme?
A. DNA polymerase
B. carbonic anhydrase
C. sodium bicarbonate
___
D. helicase
31. Which of the following is a INCORRECT
association of enzyme and substrate?
A. maltose - maltase
B. lipid - lipase
___
C. sucrose - lactase
D. acetylcholine - acetylcholinesterase
32. Enzymes bind to their substrates at any place on
the substrate.
True
False
___
33. A very high fever (105°) is dangerous because
enzymes can become denatured.
True
___
False
34. Denaturation _____.
A. changes the shape of the enzyme
B. prevents the enzyme from binding with its
substrate molecules efficiently
C. occurs at temperatures above a certain point
___
D. all of the above
35. The pH in the stomach is about 2 and the pH in
the small intestine is about 8. What will happen to
pepsin, an enzyme that
digests proteins to peptides in the stomach, when it
moves into the small intestine?
A. Pepsin will continue to function efficiently.
B. Pepsin will become denatured.
C. Pepsin's shape will change.
___
D. both B and C
36. The speed of a reaction that involves an enzyme
increases as
A. temperature decreases
B. pH becomes less than optimal
___
C. substrate concentration increases
D. all of the above
37. When a molecule binds to an enzyme at an
allosteric site, _____ inhibition occurs.
A. competitive
___
B. noncompetitive
38. Enzyme activity can be inhibited by _____.
A. a molecule that blocks its active site
B. changes in pH
C. poisons such as cyanide
D. all of the above
___
39. Symptoms of a vitamin deficiency may actually
be the result of a deficiency of a coenzyme needed to
assist enzyme
activity.
___
True
False
40. The activity of almost every enzyme in a cell is
regulated by feedback inhibition.
___
True
False