1.1. Why is meiosis impossible in the bananas we buy in the supermarket?
(A) Bananas have been genetically engineered to stop meiosis.
(B) They are polyploid and have three sets of chromosomes.
(C) Their genome is too large to undergo meiosis.
(D) They have too many transposable elements.
(E) They are blocked in the G1 phase by chemicals.
2.2. All reptiles reproduce sexually by
(A) external fertilization in which eggs are fertilized in water.
(B) external fertilization in which eggs are fertilized in a moist terrestrial environment.
(C) internal fertilization only.
(D) both internal and external fertilization.
(E) external fertilization in which the male deposits a spermatophore outside the body.
3.3. Carbon fixation requires the expenditure of ATP molecules. This ATP is generated by
(A) the Calvin cycle. (B) replenishment of the photosynthetic pigment.
(C) the light reactions. (D) the oxidative phosphorylation in mitochondria.
(E) the substrate level phosphorylation in cytosol.
5.5. Which of the following structure—function pairs is mismatched?
(A) nucleolus—ribosome production (B) lysosome—intracellular digestion
(C) ribosome—protein synthesis (D) microtubules—muscle contraction
(E) Golgi—secretion of cell products
7.7. Which of the following factors would tend to increase membrane fluidity?
(A) a greater proportion of unsaturated phospholipids
(B) a lower temperature
(C) a relatively high protein content in the membrane
(D) a greater proportion of relatively large glycolipids compared to lipids having smaller molecular weights
(E) a high membrane potential
8.8. Brian was found to be heterozygous (Ss) for sickle-cell trait. The alleles represented by the letters S and s are
(A) linked. (B) on the same chromosome but far apart. (C) on the X and Y chromosomes.
(D)on the homologous chromosomes. (E) both present in each of Brian’s sperm cells.
10.10. The sodium-potassium pump is termed electrogenic because
(A) it hydrolyzes ATP.
(B) it pumps positive charges out of the cell and negative charges into the cell.
(C) it pumps three positive charges out of the cell for every two positive charges it pumps into the cell.
(D) it pumps H+ out of the cell along with Na+.
(E) it pumps electrons into the cell.
14.14. The organisms in your backyard include trees, shrubs, grass, ants, mushrooms, birds, spiders, beetles, flies, and bacteria.
Together, all these organisms make up
(A) an ecosystem. (B) a community. (C) a population. (D) an ecosociety.
(E) an experimental group.
15.15. The main contributing factor to the release of CFC’s is
(A) decomposition in land fills. (B) acid rain. (C) emission from feedlots.
(D) leaking refrigerators and air conditioners. (E) burning of tropical forests.
19.19. Mark found an organism in a pond, and he thinks it’s a freshwater sponge. His friend Ralph thinks it looks more like an
aquatic fungus. How can they decide whether it is an animal or a fungus?
(A) See if it can swim. (B) See if it is a eukaryote or a prokaryote.
(C) Look for cell walls under a microscope. (D) Determine whether it is unicellular or multicellular.
(E) Figure out whether it is autotrophic or heterotrophic.
21.21. A major difference in the mechanism of action between steroid and peptide hormones is that
(A) steroid hormones mainly affect the synthesis of proteins, whereas peptide hormones mainly affect the activity of
proteins already in the cell.
(B) target cells react more rapidly to steroid hormones than they do to peptide hormones.
(C) steroid hormones enter the nucleus, whereas peptide hormones stay in the cytoplasm.
(D) steroid hormones bind to a receptor protein, whereas peptide hormones bind to G protein.
(E) steroid hormones affect metabolism, whereas peptide hormones affect membrane permeability.
22.22. Which of the following pairs of body systems primarily regulates the activities of the other systems?
(A) nervous and endocrine systems (B) endocrine and lymphatic systems
(C) circulatory and muscular systems (D) integumentary and nervous systems
(E) lymphatic and integumentary systems
25.25. Which of the following best illustrates homeostasis?
(A) All the cells of the body are about the same size.
(B) Most adult human beings are between 5 and 6 feet tall.
(C) The lungs and intestines have large surface areas for exchange.
(D) When oxygen in the blood decreases, you may feel light-headed.
(E) When blood salt concentration goes up, the kidney expels more salt.
26.26. A technique used in molecular systematics relies on the comparison of cytochrome c in different animals. This technique
is referred to as
(A) DNA-DNA hybridizatioin. (B) protein comparison. (C) restriction mapping.
(D) electron transport. (E) gene cloning.
27.27. Countercurrent exchange in the gills of a fish
(A) maintains a gradient that enhances diffusion.
(B) speeds up the flow of water through the gills.
(C) interferes with the efficient absorption of oxygen.
(D) means that blood and water flow in the same direction.
(E) enables the fish to obtain oxygen while swimming backward.
28.28. Which of the following is a characteristic of all organisms, but not of viruses?
(A) genetic information stored as nucleic acid (B) ability to control metabolism
(C) ability to reproduce (D) structure includes proteins
(E) plasma membrane
29.29. Researchers suspect that cytotoxic T cells are usually able to find and attack cancer cells because
(A) B cells help them. (B) cancer is induced by bacteria.
(C) cancer is an autoimmune disease. (D) cancer cells release antibodies into the blood.
(E) cancer changes the surfaces of cancerous cells.
30.30. Which of the following statements is not true?
(A) Chloroplast and mitochondria generate ATP by the same mechanism: chemiosmosis (a H+
gradient across the
(B) The inner membrane of the mitochondria translocate H+
from the intermembrane space to the matrix.
(C) Phosphorylation of ADP occurs as the H+
flow back across the membrane through the ATP synthase.
(D) ATP is made on the matrix side of the mitochondrial membrane.
(E) When ATP synthesis in chloroplast, things occur in the stroma is similar to that occurs in the matrix of mitochondria.
31.31. The extinction of plants has severe consequences because:
(A) plants do not have the extensive ranges that animals do.
(B) plants require more nutrients than animals.
(C) plants require longer periods of time to reproduce than animals.
(D) plants are more susceptible to environmental changes than animals.
(E) plants are bases of foundations of food webs.
32.32. A woman had several miscarriages. Her doctor suspected that a hormonal insufficiency was causing the lining of the uterus
to break down, as it does during menstruation, terminating her pregnancies. Treatment with which of the following might
help her remain pregnant?
(A) prolactin (B) oxytocin (C) testosterone (D) luteinizing hormone
(E) follicle-stimulating hormone
33.33. In eukaryotes, what is the active transcription generally associated with?
(A) Euchromatin only (B) Heterochromatin only (C) Highly methylated DNA only
(D)Very tightly packed DNA only (E) Both euchromatin and highly methylated DNA
35.35. Which of the following is not true of a codon?
(A) It consists of three nucleotides. (B) It may code for the amino acid as another codon does.
(C) It never codes for more than one amino acid. (D) It extends from one end of a tRNA molecule.
(E) It is the basic unit of the genetic code.
36.36. The theory that suggests that eukaryotic organelles such as mitochondria and chloroplasts may have originated from a
mutualistic relationship between two prokaryotes is referred to as
(A) eukaryotic symbiosis. (B) eukaryotic germ theory.
(C) eukaryotic coevolution. (D) eukaryotic microevolution.
(E) endosymbiotic theory.
39.39. Three kinds of selection occur that cause changes in the normal distribution of phenotypes in a population. They are
(A) directional selection, disruptive selection, and stabilizing selection.
(B) natural selection, artificial selection, and environmental selection.
(C) natural selection, genetic drift, and stabilizing selection.
(D) microevolution, macroevolution and natural selection.
(E) natural selection, artificial selection, and differential selection.
40.40. In a population that is in Hardy-Weinberg equilibrium, the frequency of the allele a is 0.2. What is the percentage of the
population that is heterozygous for this allele?
(A) 2 (B) 4 (C) 16 (D) 8 (E) 32
44.44. Important terrestrial adaptations that evolved exclusively in seed plants include all of the following except
(A) pollination by wind or animal instead of fertilization by swimming sperm.
(B) transport of water through vascular tissue.
(C) retention of the gametophyte plant within the sporophyte.
(D) dispersal of new plants by seed.
(E) protection and nourishment of the embryo within the seed.
46.46. Which of the following definitions of “Animal” is not true?
(A) Animals are multicellular eukaryotes distinguished by a specific type of heterotrophy called ingestion.
(B) In most animals, cells are successively organized into tissues, organs, and organ systems.
(C) Animal cells lack cell walls and store carbohydrate reserves as starch.
(D) Animal reproduction is primarily sexual; asexual budding or regeneration occurs in some species.
(E) Muscles and nerves, which control active behavior, are unique to animals.
47.47. Transport in plants include all of the following except
(A) absorption of water and minerals from the soil by cells of a root.
(B) that transpiration creates a force within leaves that pulls xylem sap upward.
(C) leaves exchange gases through stomata, taking in the CO2 that provides carbon for photosynthesis and expelling O2.
(D) active transport of sugar from one sieve-tube to the next.
(E) that potassium is uptaken by guard cells during stomatal opening.
48.48. A hummingbird with a beak that is too short to pollinate a flower is an example of
(A) behavioral isolation. (B) temporal isolation. (C) gametic isolation. (D) mechanical isolation.
(E) postzygotic isolation.
49.49. Antibodies of the different classes IgM, IgG, IgA, IgD and IgE differ from each other in
(A) the way they are produced. (B) the type of cell that produces them.
(C) the way they interact with the antigen. (D) the antigenic determinants that they recognize.
(E) the number of carbohydrate subunits they have.
50.50. Which of the following signal transduction molecules is not bound to the plasma membrane?
(A) G proteins (B) Phospholipase C (C) Adenylyl cyclase (D) Second messengers
(E) Receptors for peptide hormones
52.52. Which of the following is true?
(A) The leaves of both angiosperms and gymnosperms are covered by a waxy cuticle that helps to protect the leaves from
(B) Both angiosperms and gymnosperms produce ovules in a specialized structure called an ovary.
(C) “Double fertilization” to produce a fertilized egg and a triploid endosperm is characteristic of both angiosperms and
(D) The gametophyte is the dominant generation in both the angiosperms and gymnosperms.
(E) All of the statements are true.
53.53. Two animal species live in the same biome but on different continents. Although these two are not closely related, they may
appear quite similar as a result of
(A) gene flow. (B) parallel evolution. (C) convergent evolution.
(D) divergent evolution. (E) allopatric speciation.
54.54. Suppose a mutation occurred in Drosophila in the region of DNA that codes for the protein called bicoid. What is most
likely to happen during development?
(A) The fertilized egg will be bipolar.
(B) The embryos will express their father’s genotype.
(C) The polarity of the fertilized egg will be disrupted.
(D) The transcription of developmental genes will stop.
(E) Two sets of limbs will form in a mirror-image arrangement.
55.55. What is the basis for the difference in the synthesis of the leading and lagging strands of DNA molecules?
(A) The origins of replication occur only at the 5’ end of the molecule.
(B) Helicases and single-strand binding proteins work at the 5’ end.
(C) DNA polymerase can join new nucleotides only to the 3’ end of the growing strand.
(D) DNA ligase works only in the 3’ →5’ direction.
(E) Polymerase can only work on one strand at a time.
56.56. Which of the following statements about photosynthesis is not true?
(A) Photosynthesis is a redox process in which water is oxidized and carbon dioxide is reduced.
(B) There are two linked stages of photosynthesis: the light reaction and the Calvin cycle.
(C) The light reaction occurs in stroma, and the Calvin cycle occurs in grana.
(D) The Calvin cycle uses ATP for energy and NADPH for reducing power to form sugar from CO2.
(E) The flow of electron during photosynthesis is H2O→NADPH→ Calvin cycle.
58.58. The direct energy source that drives ATP synthesis during oxidative phosphorylation is
(A) the oxidation of glucose and other organic compounds.
(B) the endergonic flow of electrons down the electron transport chain.
(C) the affinity of oxygen for electrons.
(D) a difference of H+
concentration on opposite sides of the inner mitochondrial membrane.
(E) the transfer of phosphate from Krebs cycle intermediates to ATP.
59.59. Which of the following statements is a correct distinction between autotrophs and heterotrophs?
(A) Only heterotrophs need to acquire chemical compounds from the environment.
(B) Cellular respiration is unique to heterotrophs.
(C) Only heterotrophs have mitochondria.
(D) Autotrophs, but not heterotrophs, can nourish themselves beginning with nutrients that are entirely inorganic.
(E) Only heterotrophs require oxygen.
61.61. Which of the following pieces of evidence most directly contradicted the hypothesis that viruses were some kind of cell?
(A) Organisms could develop immunity to virus. (B) Viruses could pass through fine filters.
(C) Viruses can form crystals. (D) Viruses contain proteins.
(E) Viruses cause disease.
64.64. Eukaryotic promoters usually have a nucleotide sequence about 25 nucleotides upstream from the transcriptional start point.
The nucleotide sequence is called
(A) ATAT box. (B) TATA box. (C) promoter sequence. (D) TAATTAT sequence.
(E) Shine-Dalgarno sequence.