Life on Earth Practice Test, Exams of Human Geography

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BIOA01H3 F Life on Earth TERM 1 PRACTICE TEST

(ACTUAL POSSIBLE QUESTIONS AND ANSWERS NEW

UPDATE) University of Toronto

Here are 60 Practice Questions so you can have an idea of the kind of questions that

are likely to be asked on Term Test # 1.

1. Which of the following is a correct sequence for the biological classification of organisms?

A. genus, species, family, order, class, phylum, kingdom

B. genus, species, family, order, class, kingdom, phylum

C. genus, species, order, family, class, phylum, kingdom

D. species, genus, order, family, class, kingdom, phylum

E. species, genus, family, order, class, phylum, kingdom

2. Which structure is common to plant and animal cells?

A. chloroplast

B. wall made of cellulose

C. central vacuole

D. mitochondrion

E. centriole

3. Which of the following is true for all exergonic reactions?

A. The products have more total energy than the reactants.

B. The reaction proceeds with a net release of free energy.

C. Some reactants will be converted to products.

D. A net input of energy from the surroundings is required for the reactions to proceed.

E. The reactions are non-spontaneous.

4. Which of the following would likely move through the lipid bilayer of a plasma membrane

most rapidly?

A. CO 2

B. an amino acid

C. glucose

D. K

E. starch

5. Which of the following statements describes NAD

?

A. NAD

has more chemical energy than NADH+H

.

B. NAD

is reduced to NADH+H

during both glycolysis and the citric acid cycle.

C. NAD

is reduced by the action of hydrogenases.

D. NAD

can donate electrons for use in substrate-level phosphorylation.

E. In the absence of NAD

, glycolysis can still function.

12. The immediate energy source that drives ATP synthesis by ATP synthase during oxidative

phosphorylation is

A. the oxidation of glucose and other organic compounds.

B. the flow of electrons down the electron transport chain.

C. the affinity of oxygen for electrons.

D. the H concentration gradient across the inner mitochondrial membrane.

E. the transfer of phosphate to ADP.

13. Some bacteria are metabolically active in hot springs because

A. they are able to maintain a cooler internal temperature.

B. high temperatures make catalysis unnecessary.

C. their enzymes have high optimal temperatures.

D. their enzymes are completely insensitive to temperature.

E. they use molecules other than proteins or RNAs as their main catalysts.

14. Which of the following factors would tend to increase membrane fluidity?

A. a greater proportion of unsaturated phospholipids

B. a greater proportion of saturated phospholipids

C. a lower temperature

D. a relatively high protein content in the membrane

E. a greater proportion of relatively large glycolipids compared with lipids having

smaller molecular masses

15. What is the reducing agent (or electron donor) in the following reaction?

A. oxygen

B. NADH+H

Pyruvate + NADH + H

→ Lactate + NAD

C. NAD

D. lactate

E. pyruvate

16. Reactants capable of interacting to form products in a chemical reaction must first overcome

a thermodynamic barrier known as the reaction's

A. entropy.

B. activation energy.

C. endothermic level.

D. heat content.

E. free-energy content.

17. What does the chemiosmotic process in mitochondria involve?

A. establishment of a proton gradient

B. diffusion of electrons through the thylakoid membrane

C. reduction of water to produce ATP energy

D. movement of water by osmosis into the intermembrane space from the matrix

E. oxidation of glucose, releasing carbon dioxide, NADH+H

, and FADH 2

18. Which of the following processes includes all others?

A. osmosis

B. diffusion of a solute across a membrane

C. facilitated diffusion

D. passive transport

E. transport of an ion down its electrochemical gradient

19. Choose the pair of terms that correctly completes this sentence: Catabolism is to anabolism as

is to.

A. exergonic; spontaneous

B. exergonic; endergonic

C. free energy; entropy

D. work; energy

E. entropy; enthalpy

20. Active transport involves all of the following except the

A. diffusion of solute through the lipid bilayer of a membrane.

B. transport of solute against a concentration gradient.

C. a specific transport protein in the membrane.

D. pumping of solutes across the membrane.

E. hydrolysis of ATP.

21. When electrons move closer to a more electronegative atom, what happens?

A. Energy is released.

B. Energy is consumed.

C. The more electronegative atom is reduced.

D. The more electronegative atom is oxidized.

E. A and C are correct.

22. If an enzyme solution is saturated with substrate, the most effective way to obtain a faster yield

of products is to

A. add more substrate.

B. add more of the enzyme.

C. heat the solution to 90°C.

D. add an allosteric inhibitor.

E. add a noncompetitive inhibitor.

23. Which metabolic pathway is common to both fermentation and cellular respiration of a

glucose molecule?

A. the citric acid cycle

B. the electron transport chain

C. glycolysis

D. synthesis of acetyl CoA from pyruvate

E. reduction of pyruvate to lactate

30. When a glucose molecule loses a hydrogen atom as the result of an oxidation-reduction

reaction, the molecule becomes

A. dehydrogenated.

B. hydrogenated.

C. reduced.

D. oxidized.

E. an oxidizing agent.

31. Which type of bond must be broken for water to vaporize?

A. ionic bonds

B. nonpolar covalent bonds

C. polar covalent bonds

D. hydrogen bonds

E. covalent bonds

32. Where does glycolysis takes place?

A. mitochondrial matrix

B. mitochondrial outer membrane

C. mitochondrial inner membrane

D. mitochondrial intermembrane space

E. cytosol

33. What must be the difference (if any) between the structure of ATP and the structure of

the precursor of the A nucleotide in RNA?

A. The sugar molecule is different.

B. The nitrogen-containing base is different.

C. The number of phosphates is three instead of one.

D. The number of phosphates is three instead of two.

E. There is no difference.

34. Which of the following intermediary metabolites enters the citric acid cycle and is formed, in

part, by the removal of a carbon (CO 2

) from one molecule of pyruvate?

A. lactate

B. oxaloacetate

C. glyceraldehydes-3-phosphate

D. acetyl CoA

E. citrate

35. When two atoms are equally electronegative, what type of bond will form?

A. hydrophobic

B. polar covalent

C. ionic

D. nonpolar covalent

E. hydrogen

36. There are 20 different amino acids. What makes one amino acid different from another?

\

A. different carboxyl groups attached to an alpha-carbon

B. different amino groups attached to an alpha-carbon

C. different side chains (R groups) attached to an alpha-carbon

D. different alpha-carbons

E. different asymmetric carbons

37. How many carbon atoms are fed into the citric acid cycle as a result of the oxidation of

one molecule of pyruvate?

A. 2

B. 4

C. 6

D. 8

E. 10

38. 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 transported to specific organs such as the brain.

C. It is used to store energy as more ATP.

D. It is used to generate ADP from nucleotide precursors.

E. It is lost to the environment.

39. The final electron acceptor of the electron transport chain that functions in aerobic

oxidative phosphorylation is

A. oxygen.

B. water.

C. NAD

D. pyruvate.

E. ADP.

46. Where is free energy released during the electron transport chain of cellular respiration?

A. Only at the end, when O 2

is converted to H 2

O.

B. Each time a carrier is oxidized.

C. Only at the beginning, when NADH+H

is converted to NAD

.

D. Each time a carrier is reduced.

E. Only when FADH 2

is converted to FAD.

47. Which term includes all others in the list?

A. monosaccharide

B. disaccharide

C. starch

D. carbohydrate

E. polysaccharide

48. Which of the following statements describes NAD+?

A. NAD

is reduced to NADH + H

during both glycolysis and the citric acid cycle.

B. NAD

has more chemical energy than NADH + H

.

C. NAD

is reduced by the action of hydrogenases.

D. NAD

can donate electrons for use in substrate- level phosphorylation.

E. In the absence of NAD

, glycolysis can still function.

49. When electrons flow along the electron transport chains of mitochondria, which of the

following changes occurs?

A. The pH of the matrix decreases.

B. ATP synthase moves protons by facilitated diffusion.

C. The electrons gain free energy.

D. The cytochromes phosphorylate ADP to form ATP.

E. NAD

is oxidized.

50. Which of the following statements about glycolysis is false?

A. Glycolysis proceeds indefinitely as long as glucose is available.

B. The enzymes of glycolysis are located in the cytosol of the cell.

C. Glycolysis can operate in the complete absence of O 2.

D. The end products of glycolysis are ATP, pyruvate and NADH+H

.

E. Glycolysis makes ATP through substrate-level phosphorylation.

51. The light reactions of photosynthesis supply the Calvin cycle with

A. light energy.

B. CO

and ATP.

C. H

O and NADPH.

D. ATP and NADPH.

E. sugar and O 2

52. Which of the following sequences correctly represents the flow of electrons

during photosynthesis?

A. NADPH → O

→ CO

B. H

O → NADPH → Calvin cycle

C. NADPH → chlorophyll → Calvin cycle

D. H

O → photosystem I → photosystem II

E. NADPH → electron transport chain → O 2

53. In mechanism, photophosphorylation is most similar to

A. substrate-level phosphorylation in glycolysis.

B. oxidative phosphorylation in cellular respiration.

C. the Calvin cycle.

D. carbon fixation.

E. reduction of NADP

54. How is photosynthesis similar in C 4

and CAM plants?

A. In both cases, only photosystem I is used.

B. Both types of plants make sugar without the Calvin cycle.

C. In both cases, Rubisco is not used to fix carbon initially.

D. Both types of plants make most of their sugar in the dark.

E. In both cases, thylakoids are not involved in photosynthesis.

55. Which of the following does not occur during the Calvin cycle?

A. carbon fixation

B. oxidation of NADPH

C. release of oxygen

D. regeneration of the CO 2

acceptor

E. consumption of ATP

56. Photosynthesis ceases when leaves wilt, mainly because

A. the chlorophyll of wilting leaves breaks down.

B. flaccid mesophyll cells are incapable of photosynthesis.

C. stomata close, preventing CO 2 from entering the leaf.

D. photolysis, the water-splitting step of photosynthesis, cannot occur when there is a

water deficiency.

E. accumulation of CO 2 in the leaf inhibits enzymes.

57. Active transport involves all of the following except the

A. diffusion of solute through the lipid bilayer of a membrane.

B. pumping of solutes across the membrane.

C. hydrolysis of ATP.

D. transport of solute against a concentration gradient.

E. a specific transport protein in the membrane.