Reference no: EM13121444

Practice test that I don't have the correct answers for. I would just like to double check myself.
Exam 2A 2007
1. Biological order
a. violates the first and second laws of thermodynamics
b. is dependent upon organisms being closed systems
c. is consistent with the second law of thermodynamics
d. can be seen in individual organisms but not whole populations
e. more than one of the above

2. A series of enzymes catalyze the reactions X ? Y ? Z ? A. Substance A can bind to the enzyme that converts X to Y at a location distant from its active site. Substance "A" functions as
a. a competitive regulator
b. a substrate
c. an intermediate
d. an allosteric regulator
e. a coenzyme

3. A yeast cell utilizes 8 molecules or glucose for energy production. No oxygen is available. What is the maximum yield of ATP?
a. 32 b. 24 c. 16 d. 8 e. 36 or 38

4. How does an enzyme catalyze a reaction:
a. by supplying energy to speed up the reaction
b. by lowering the free energy of the reaction
c. by lowering the energy of activation
d. by increasing free energy of the reaction
e. both b and c above are correct

5. Whenever energy is transformed there is always an increase
a. in the free energy of the system
b. in the free energy of the universe
c. in the entropy of the system
d. in the entropy of the universe
e. in the enthalpy of the universe

6. The pH of the of the chloroplast thylakoid compartment:
a. is equal to the pH of the cytoplasm
b. is greatest than the pH of the stroma
c. is less than the pH of the stroma
d. is equal to the pH of the stroma
e. none of the above

7. Glucose diffuses slowly through artificial phospholipid bilayers because of its size and polarity. Cells of the intestine, however, rapidly move large quantities of glucose form the digested food outside the cell into their glucose-poor cytoplasm. Which transport mechanism is most probably functioning in these intestinal cells?
a. facilitated diffusion b. endocytosis c. staple diffusion d. active transport e. osmosis

8. The kinds of molecules that pass through a cell membrane with most difficulty are
a. large and hydrophobic b. small and hydrophobic c. large polar molecules
d. monosaccharides such as glucose e. ions

9. The data in this figure are form an experiment in which the rate of photosynthesis (PHS) has been measured in two plants (UD and BR) under conditions of increasing levels of oxygen in the air. From these data you could conclude (Figure)
a. UD has only the dark reactions of photosynthesis
b. UD is a C3 plant and BR is a C4 plant
c. UD is a C4 plant and BR is a C3 plant
d. Only UD has the light reactions of photosynthesis
e. Only BR has the Calvin cycle

10. An animal cell places in a hypotonic solution will
a. increase in volume
b. decrease in volume
c. show no change in volume
d. initially increase, then decrease in volume
e. initially show no change, then increase in volume

11. Fluidity of membranes is decreased by
a. increasing the normal number of covalent bonds between membrane phospholipids
b. increasing the membrane content of phospholipids with saturated fatty acids
c. increasing their temperature
d. decreasing their temperature
e. more than one of the above is correct

12. Which of the following best characterizes membrane structure?
a. rigidity and water repellence
b. enzymes and ATP
c. passive and active
d. streaming and unorganized
e. asymmetry and fluidity

13. The movement of uncharged solute molecules form an area of lower concentration to an area of higher concentration is best described by
a. diffusion b. exocytosis c. active transport d. osmosis e. facilitated diffusion

14. The oxygen consumed during cellular respirations is directly involved in
a. glycolysis b. accepting electrons c. the Krebs cycle
d. the oxidation of pyruvate to acetyl CoA e. the phosphorylation of ADP

15. What type of poisonous agent would most directly interfere with glycolysis?
a. an agent that reacts with oxygen and reduces the concentration in the cell
b. an agent that binds to pyruvate and inactivates it
c. an agent structurally similar to glucose but unable to be catabolized
d. an agent that reacts with NADreduced and converts it to NAD+
e. an agent that inhibits the formation of acetyl coenzyme A

16. Figure: In which location is pyruvate synthesized?
17. Figure: Where are the enzymes of the citric acid cycle located?
18. Figure: Where are the electron transport carriers located?

19. Which of the following is true for endergonic reactions?
a. the products have more free energy than the reactants
b. the products have less free energy than the reactants
c. reactants will be converted completely to products
d. a net input of energy is required for the reaction to proceed
e. none of the above are correct

20. Which process in eukaryotic cells will proceed whether O2 is present or not?
a. electron transport
b. fermentation
c. oxidative phosphorylation
d. glycolysis
e. Krebs cycle

21. Which of the following statements are correct:
a. ATP serves as the main energy carrier in cells
b. ATP can drive endergonic reactions in cells
c. The regeneration of ATP from ADP and phosphate is an exergonic reaction

a. a only b. b only c. c only d. a and b only e. a, b, an c are correct

22. The color of light LEAST effective in stimulating photosynthesis is:
a. blue b. red c. orange d. yellow e. green

23. The chlorophyll termed P700 is reduced by electrons from
a. photosystem I
b. water
c. photsystem II
d. NADPreduced
e. accessory pigments

24. The chemiosmosis process in chloroplasts involves the
a. establishment of a protein gradient
b. diffusion of electrons through the thylakoid membrane
c. oxidation of water
d. movement of water by osmosis into the thylakoid
e. fixation of carbon dioxide

25. The initial reaction of the Calvin cycle
a. generates 3 molecules of a two carbon sugar
b. occurs in association with the thylakoid membrane
c. produces a molecule of carbon dioxide
d. requires a three carbon substrate molecule
e. involves carbon fixation

26. Which term most precisely describes the general process of converting small molecules into larger more complex ones?
a. catalysis b. metabolism c. anabolism d. dehydration e. catabolism

27. Endocrine signaling
a. occurs only in paracrine yeast cells
b. has been found in plants but not animals
c. involves chemical signals acting on cells near the secreting cell
d. involves chemical signals acting across a relatively long distance
e. more than one of the above are correct

28. From the perspective of the cell receiving the message, the three stages of cell signaling are
a. paracrine, synaptic and hormonal
b. reception, transduction and response
c. reception, response and division
d. alpha, beta and gamma
e. reception, generation and disintegration

29. Of the following, a receptor protein in a membrane that recognizes a chemical signal is more similar to
a. genes in the genome
b. an enzyme with an optimum pH and temperature for activity
c. a metabolic pathway in an organelle
d. an enzyme that binds a specific substrate
e. none of these answers is similar to a receptor protein

30. When a DNA forms from nucleotides, the following changes apply:
a. +?H, +?S, +?G b. -?H, +?S, +?G c. +?H, -?S, -?G
d. +?H, -?S, +?G e. -?H, -?S, +?G

31. Equilibrium is reached in an aqueous solution when
a. random thermal motion cease
b. solute and solvent molecules are moving at the same rate
c. dissolves solutes and solvent are equally distributed
d. molecular motion stops
e. there are the same number of solute and solvent molecules in the solution

32. Which of the following is an oxidized compound?
a. NADPH b. FADH c. NADH d. NAD+ e. more than one of the above

33. - 35. Which compounds in the lettered list are associated with the numbered pathways?
a. NAD
b. FAD
c. NADP
d. a and b above
e. none of the above

33. photosynthesis
34. citric acid cycle
35. fermentation

36. Increasing substrate concentration in an enzymatic reaction could overcome which of the following?
a. denaturation of an enzyme
b. allosteric inhibition of an enzyme
c. competitive inhibition of an enzyme
d. noncompetivie inhibition of an enzyme
e. lack of cofactors for an enzyme

37. Because bundle sheath cells are relatively protected from atmospheric oxygen, the level of _________ is held to a minimum in C4 plants.
a. glycolysis
b. light reactions
c. oxidative phosphorylation
d. cylic electron flow
e. photorespiration

38. According to the fluid-mosaic model of cell membranes, which of the following is a true statement about membrane proteins?
a. they have hydrophilic tails which occupy the interior of the membrane
b. they have frequently leave the membrane and dissolve in the surrounding fluid
c. they are mainly structural, having few, if any, specific functions
d. they often flip-flop form the exterior half of the bilayer to the interior half
e. they can be classified as either integral or peripheral

39. The light reactions of photosynthesis in eukaryotes:
a. utilize thylakoids as the principal pigment
b. occur in the chloroplast stroma
c. generate oxygen
d. require an initial input of ATP
e. more than one of the above is correct

40. In addition to ATP, what are the end products of glycolysis?
a. carbon dioxide and water
b. carbon dioxide and ethanol
c. water and ethanol
d. carbon dioxide and reduced NAD
e. pyruvate and reduced NAD