5 Written questions
5 Matching questions
In this reaction, the reactant (s) are _____________ and the coenzyme NAD is ____________.
A. reduced; oxidized
B. oxidized; oxidized
C. reduced; reduced
D. oxidized; reduced
- Which of the following is consistent with the laws of physics governing energy?
A. When a liter of gasoline is burned in a car engine, 100% of its energy goes into moving the car along the road.
B. You eat a "quarter-pounder" hamburger and assemble exactly a quarter-pound of additional body weight on your body.
C. Eventually sunlight that is absorbed on the earth returns to space as dispersed heat.
D. A calorie of sunlight becomes a calorie of plant tissue that, eaten by you, becomes a calorie of heat lost in muscle "power."
E. Chemical bonds are a case of converting energy to matter; breaking the bonds converts matter to energy.
- Endergonic reactions:
A. release energy.
B. have a negative ΔG and occur spontaneously.
C. can only occur if there is an input of energy.
D. have products with less free energy than the reactants.
E. All of the choices are correct.
- Of the following, which process will not denature a protein?
A. heating to temperatures above 100 C
B. addition of strong acids or strong bases
D. addition of distilled water
- 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 D. oxidized; reduced
- b C. Eventually sunlight that is absorbed on the earth returns to space as dispersed heat.
- c C. can only occur if there is an input of energy.
- d D. addition of distilled water
- e B. The reaction will continue, since the enzyme is not consumed by the reaction.
5 Multiple choice questions
- C. A; E and F
- D. D refers to the product.
- C. Energy of activation
- A. have increased greatly.
5 True/False questions
In this pathway, B C is coupled with ADP ATP. Categorize the reactions as endergonic or exergonic.
A. B C is endergonic and ADP ATP is exergonic.
B. ADP ATP is endergonic and B C is exergonic.
C. Both B C and ADP ATP are endergonic.
D. Both B C and ADP ATP are exergonic. → B. ADP ATP is endergonic and B C is exergonic.
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.
D. lead. → D. lead.
If a change in pH alters an allosteric site where an inhibitor binds, but doesn't change the active site for the intended substrate, it would be possible for an enzymatically controlled reaction to occur as normal.
True False → True
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 → A. kinetic energy: fat molecules
Which best describes the first law of thermodynamics?
A. Energy is changed from one form to another with a loss of usable energy.
B. Energy is not created nor destroyed, but it can change from one energy form to another.
C. Energy can be created from matter or used to produce matter.
D. Some useful energy is lost as heat whenever an energy transfer occurs.
E. Energy transfers are always 100% efficient in changing energy from one useful form to another. → D. Some useful energy is lost as heat whenever an energy transfer occurs.