Ch. 8 Quiz

Question 1

The second law of thermodynamics holds that…

Answer 1

Energy of one form is converted to a less concentrated whenever energy is transformed or transferred

Question 2

Which term most precisely describes the cellular process of breaking down large molecules into smaller ones?

Answer 2

Catabolism

Question 3

Whenever energy is transformed, there is always an increase in the

Answer 3

Entropy of the universe

Question 4

Which of the following is an example of potential rather than kinetic energy?

A) the muscle contractions of a person mowing grass
B) water rushing over Niagara Falls
C) light flashes emitted by a firefly
D) a molecule of glucose
E) the flight of an insect foraging for food

Answer 4

a molecule of glucose

Question 5

Which of the following is most similar in structure to ATP?

A) a pentose sugar
B) a DNA nucleotide
C) an RNA nucleotide 
D) a phospholipid
E) an amino acid with three phosphate groups attached

Answer 5

an RNA nucleotide

Question 6

Which of the following statements is true about enzyme-catalyzed reactions?

A) The reaction is faster than the same reaction in the absence of the enzyme
B) The free energy change of the reaction is opposite from the reaction that occurs in the absence of the enzyme
C) The reaction always goes in the direction toward chemical equilibrium
D) Enzyme-catalyzed reactions require energy to activate the enzyme
E) Enzyme-catalyzed reactions release more free energy than noncatalyzed reactions

Answer 6

A) the reaction is faster than the same reaction in the absence of the enzyme

Question 7

Increasing the substrate concentration in an enzymatic reaction could overcome which of the following?

Answer 7

Competitive inhibition

Question 8

Zinc, an essential trace element for most organisms, is present in the active site of the enzyme carboxypeptidase. The zinc most likely functions as a…

Answer 8

A cofactor necessary for enzyme activity

Question 9

When sodium chloride (table salt) crystals dissolve in water, the temperature of the solution decreases. This means that, for dissociation of Na+ and Cl- ions…

Answer 9

the change in enthalpy is positive, but the change in entropy is greater

Question 10

Which enzymes may translocate from the cytoplasm to associate with the cytoplasmic face of the plasma membrane in response to a signal?

Answer 10

phospholipid hydrolases