Home Work for Chapter 6
TruelFalse
If the statement is true, write a T in the blank. If the statement is false, make it correct by changing the under- lined
word(s) and writing the correct word(s) in the answer blank.
1. _______ The first law of thermodynamics states that entropy is constantly increasing in the universe.
2. _______ At rest your body steadily gives off heat equal to that from a 100-watt light bulb.
3. _______ W hen you eat a potato, some of the stored chemical energy of the food is converted into kinetic
energy that moves your muscles.
4. _______ Energy is the capacity to accomplish work.
5. _______ The amount of low-quality energy in the universe is decreasing.
Matching
In the blank preceding each item, indicate if the first law of thermodynamics (1) or the second law of thermodynamics (2) is best described.
6. _______ Cooling of a cup of coffee.
7. _______ Evaporation of gasoline into the atmosphere.
8. _______ A hydroelectric plant at a waterfall, producing electricity.
9. _______ The creation of a snowman by children.
10. _______The glow of an incandescent bulb following the flow of electrons through a wire.
11. _______A typesetter arranging the type for a page of a biology textbook.
12. _______The movement of a gas-powered automobile.
13. _______The glow of a firefly.
14. _______Humans running the 100-meter dash following their usual food intake.
15. _______The death and decay of an organism.
Fill-in-the-Blanks
For questions 16-20, choose from these possibilities:
(a) chemical energy
(b) entropy
(c) heat
(d) kilocalorie
(e) metabolism
16.________ is a measure of the amount of disorder in a system.
17. _______ includes all of the activities by which a cell acquires energy and materials and uses them to build
break apart, store, and release substances in controlled processes that are typical for that cell.
18.______ The measure of energy that can heat 1,000 grams of water from 14.5C to 15.5C at standard
pressure is
19.______ is the potential energy stored in the attractive forces (bonds) that cause atoms to group together into
molecules.
20. _____ that results from collisions among molecules and their surroundings is a kind of kinetic energy also
called thermal energy.
Fill-in-the-Blanks
The substances present at the end of a chemical reaction, the (1) ___________________, may have less or more
energy than did the starting substances, the (2)___________________. Reaction are (3) _____________ in that
they can proceed in forward and reverse directions. Such reactions tend to approach chemical (4)
_____________, a state in which the reaction are proceeding at about the same (5) ____________________, in
both direction.
Labeling
Classify each of the following reactions as endergonic or exergonic.
26. __________________ Burning wood at a campfire.
27. __________________ The products of a chemical reaction have more energy than the reactants.
28. __________________Glucose + oxygen ----> carbon dioxide + water plus energy
29. __________________The reactants of a chemical reaction have more energy than the product. _10. The
reaction releases energy.
Matching
Choose the one most appropriate answer for each.
_______ metal ions
_______ FAD
_______ coenzymes
A. Large organic molecules; derived in part from vitamins; transfer hydrogens and
electrons
B. A coenzyme, nicotinamide adenine dinucleotid phosphate; in reduced form
carries H+ and electrons to other reaction sites
C. A coenzyme, nicotinamide adenine transfers hydrogens and electrons to other
reaction sites
D. Example: Fe++ serves as a cofactor and is a component of enzymatic
cytochromes
_______ NADP+
_______ NAD+
E. A coenzyme, flavin adenine dinucleotide; transfers hydrogens and electrons to
other reaction sites
Labeling
Study the diagram at the right; choose the most
appropriate answer for each: A or B.
1. _________ degradative reaction
2._________ an endergonic reaction
3._________ a biosynthetic reaction
4._________ an exergonic reaction reactants
Matching
Match the items on the sketch below with the list of descriptions. Some answers may require more than one letter.
16. ___________
17. ___________
18. ___________
19. ___________
20. ___________
21. ___________
A. Transition state, the time of
the most precise fit between
enzyme and substrate
B. Complementary active site of the enzyme
C. Enzyme, a protein with catalytic power
D. Product or reactant molecules that an enzyme can specifically recognize
E. Product or reactant molecule
F. Bound enzyme-substrate complex
___1. An important principle of the 2 nd law of
Thermodynamic states that _______.
A. energy can be transformed into matter, and
therefore we can get something for nothing
B. energy can only be destroyed during nuclear
reactions, such as those that occur inside the sun.
C. if energy is gained by one region of the universe,
another place in the univers also must gain energy
in order to maintain the balance of nature.
D. matter tends to become increasingly more
disorganized.
___2. Essentially, the firs law of thermodynamics state
that _____.
A. One form of energy cannot be converted into
another
B. entropy is increasing in the universe
C. energy cannot be created or destroyed
D. energy cannot be converted into matter or matter
into energy.
___3. An enzyme is best described as ____.
A. an acid B. protein C. a catalyst D. a fat
E. both b and c
4. W hich is not true of enzyme behavior?
A. enzyme shape may change during catalysis
B. the active site of an enzyme orients it substrate
molecules, thereby promoting interaction of their
reactive parts.
C. all enzymes have an active site where substrates
are temporarily bound.
D. an individual enzyme can catalyze a wide variety
of different reactions
5. W hen NAD + combines with hydrogen, the
NAD + is ____.
A. reduced B. oxidized C. Phosphorylated
D. denatured
6. A substance that gains electron is ____.
A. Oxidized B. a catalyst C. reduced D. a substrate
7. In ____ pathways, carbohydrates, lipids, and proteins
are broken down in stepwise reactions that lead to
products of lower energy.
A. intermediate B. biosynthetic C. induce
D. degradative
8. As to major function, NAD +, FAD, and NADP + are
classified as ____.
A. enzymes
B. phosphate carriers.
C. cofactors that function as coenzymes
D. end products of metabolic pathways
9. W hen a phosphate bond is linked to ADP, the bond
_____.
A. absorbs a large amount of free energy when the
phosphate group is attached during hydrolysis
B. is formed when ATP is hydrolyzed to ADP
and one phposphate group
C. is usually fournd in each glucose molecule;
that is why glucose is chosen as the starting
point for glycolysis
D. releases a large amount of usable energy when
the phopshate group is split off during hydrolysis.
10. An allosteric enzyme_____.
A. has an active site where substrate molecules bind
and another site that binds with intermediate or
end product molecules.
B. is an important energy carrying nucleotide
C. carries out either oxidation reactions or reduction
reactions but not both
D. raises the activation energy of the chemical
reaction it catalyzes.