blackboard quiz 2 MC Flashcards
Biological membranes form because phospholipids are: A. Hydrophilic B. Hydrophobic C. Have bends in their fatty acid tails D. Amphipathic E. Hydrocarbons
D amphipathic
Which of the following statements is correct about diffusion?
A. It is very rapid over long distances.
B. It requires an expenditure of energy by the cell.
C. It is a process in which molecules move from a region of higher concentration to a region of lower concentration.
D. It is a process in which molecules move from a region of lower concentration to one of higher concentration.
E. It requires integral proteins in the cell membrane.
c it is a process in which molecules move from a region of lower concentration to one of higher concentration
Which of the following would likely move through the lipid bilayer of a plasma membrane most rapidly?
A.
Carbon dioxide (CO2)
B. An amino acid C. Glucose
D. Potassium ion (K+)
E. Starch
A. carbon dioxide
Which of the following is a characteristic feature of a carrier protein in a plasma membrane?
A. It is a peripheral membrane protein. B. It exhibits a specificity for a particular type of molecule. C. It requires the expenditure of cellular energy to function. D. It works against diffusion. E. It has few, if any, hydrophobic amino acids.
B.
It exhibits a specificity for a particular type of molecule.
When you have a severe fever, what grave consequence may occur if it is not controlled?
A. Destruction of your enzymes’ primary structure B. Removal of amine groups from your proteins C. Change in the tertiary structure of your enzyme D. Removal of the amino acids in active sites of your enzymes E. Binding of your enzymes to inappropriate substrates
C.
Change in the tertiary structure of your enzyme
When glucose monomers are joined together by glycosidic linkages to form a cellulose polymer, the changes in free energy and entropy of the product formed as compared to the reactants are as follows
A. \+ΔG, +ΔS B. \+ΔG, -ΔS C. -ΔG, -ΔS D. -ΔG, +ΔS E. No change in free energy or entropy
B.
+ΔG, -ΔS
Which of the following is TRUE of anabolic pathways?
A. They contain a series of reactions that occur spontaneously B. They typically do not require the action of enzymes C. They require energy from outside the system to build up polymers from monomers D. They consume energy which then decreases entropy in the universe E. Energy is released as polymers are broken down into monomers
c. they require energy from outside the system to build up polymers from monomers
Which of the following best represents the 1st law of thermodynamics?
A. Entropy in the universe is always decreasing
B. Entropy in the universe is constant
C. Kinetic energy is stored energy that results from the specific arrangement of matter
D. Energy is neither created nor destroyed
E. Energy can not be transferred nor transformed
D. Energy is neither created nor destroyed
When chemical, transport, or mechanical work is done by an organism, what happens to the heat generated?
A. It is used to power yet more cellular work
B. It is used to store energy as more ATP
C. It is used to generate ADP from nucleotide precursors
D. It is released in to the environment
E. It is transported to specific organs such as the brain
D. It is released in to the environment
Living organisms increase in complexity as they grow, resulting in a decrease in the entropy of an organism. How does this relate to the second law of thermodynamics?
A. Living organisms do not obey the second law of thermodynamics, which states that entropy must increase with time B. Life obeys the second law of thermodynamics because the decrease in entropy as the organism grows is exactly balanced by an increase in the entropy of the universe C. Living organisms only follow the first law of thermodynamics D. As a consequence of growing, organisms cause a greater increase in entropy in the environment than the decrease in entropy associated with their growth E. Living organisms are able to transform energy into entropy
D. As a consequence of growing, organisms cause a greater increase in entropy in the environment than the decrease in entropy associated with their growth
Which term most precisely describes the cellular process of breaking down large molecules into smaller ones? A. Catalysis B. Metabolism C. Catabolism D. Dehydration E. Anabolism
C. Catabolism
The active site of an enzyme is the region that
A. Binds non-competitive regulators of the enzyme
B. Is involved in the catalytic reaction of the enzyme
C. Binds competitive regulators of the enzyme
D. A and B are correct statements
E. B and C are correct statements
E. B and C are correct
Which of the following types of reactions would decrease the entropy within a cell?
A. Anabolic reactions B. Catabolic reactions C. Hydrolytic reactions D. Reactions involving the digestion of food E. More than one of the above statements is correct
A. Anabolic reactions
During a laboratory experiment, you discover that an enzyme-catalyzed reaction has a ∆G of -20 kcal/mol. If you double the amount of enzyme in the reaction, what will be the ∆G for the new reaction? A. -40 kcal/mol B. -20 kcal/mol C. 0 kcal/mol D. +20 kcal/mol E. +40 kcal/mol
B. -20kcal/mol
Which of the following statements is TRUE about enzyme-catalyzed reactions?
A. The reaction proceeds 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 dononcatalyzed reactions
a. the reaction proceeds faster than the same reaction in the absence of the enzyme
