5 Written Questions
5 Matching Questions
- Which form of energy is NOT correctly associated with the related example?
A. kinetic energy: fat molecules
B. kinetic energy: movement of muscles
C. chemical energy: glucose
D. potential energy: water held behind a dam
E. potential energy: ATP
- Which statement is NOT true about the effects of various conditions on the activity of an enzyme?
A. Higher temperatures generally increase the activity of an enzyme up to a point.
B. Above a certain range of temperatures, the protein of an enzyme is denatured.
C. A change in pH can cause an enzyme to be inactivated.
D. An enzyme's activity is generally reduced by an increase in substrate concentration.
E. When sufficient substrate is available, the active site will nearly always be occupied.
The metabolic pathway at right involves how many possible chemical reactions?
- The activity of an enzyme might be increased by all of the following except ________?
A. increase in substrate concentration.
B. a vitamin.
C. 2-4 degree increase in temperature.
Identify the graph that depicts the reaction C→D.
- a A. five
- b B.http://www.flickr.com/photos/60296733@N06/5514033968/
- c A. kinetic energy: fat molecules
- d D. lead.
- e D. An enzyme's activity is generally reduced by an increase in substrate concentration.
5 Multiple Choice Questions
- C. a molecule that carries a great deal of chemical energy in a chemical bond.
- E. are about twelve enzymes, at least one responsible for each step in the metabolic pathway.
- C. can only occur if there is an input of energy.
- D. All of the choices are true.
- D. All of the choices are correct.
5 True/False Questions
Astrophysicists explain that eventually the sun will swell to become a red giant, engulf the earth and "burn out" with all forms of energy dispersing in a final "heat death." Compared with conditions today, the entropy of the universe then will
A. have increased greatly.
B. have decreased greatly.
C. remain the same because energy cannot be created or destroyed. → False
A coenzyme is
A. an ionic cofactor that interacts with an enzyme to allow it to work.
B. a protein cofactor that interacts with an enzyme to allow it to work.
C. a nonprotein organic cofactor that interacts with an enzyme to allow it to work.
D. an ionic cofactor that interacts with an enzyme to inhibit it.
E. a protein cofactor that interacts with an enzyme to inhibit it. → E. Both taking lactase enzyme and avoiding all dairy products would be correct.
ATP is considered a high-energy compound because under cellular conditions, 7.3 kcal per mole of energy is released when a bond is broken between:
A. the base adenine and the sugar ribose.
B. the adenosine and the phosphate groups.
C. the base adenine and the phosphate groups.
D. the adenosine diphosphate and the third phosphate.
E. All of the bonds release energy as ATP is completely broken down. → C. a molecule that carries a great deal of chemical energy in a chemical bond.
While eating a container of yogurt, you have to leave, so you store the yogurt in the refrigerator. A day later you return and find the surface of the yogurt is no longer smooth but has broken into several liquified products. You correctly guess that enzymes from your saliva, via the spoon, have continued digesting the yogurt in your absence. What will happen over time?
A. The reaction will soon stop because the amount of saliva is small, and you would have to add more saliva to continue the degradation.
B. The reaction will continue, since the enzyme is not consumed by the reaction.
C. The reaction will continue until half is digested and then stop because the reaction between substrate and product will be balanced.
D. Absolutely no degradation of the yogurt will occur naturally unless in the presence of this enzyme. → A. the cellular energy expended in "thinking" must be less than the chemical bond energy supplied in food to these brain cells.
In the electron transport systems of chloroplasts and mitrochondria,
A. the system consists of a series of membrane bound carriers that transfer electrons from one carrier to another.
B. high energy electrons enter the system and low energy electrons exit the system.
C. energy release occurs when the electron transfers from one carrier to another.
D. All of the choices are correct. → D. addition of distilled water