Name: ______________________________________ Hour: ____________ Date: ________________

A.P. Biology : 1st Semester Exam Practice Exam I.

Multiple Choice. 1. ______In the process of photosynthesis, free oxygen is liberated from ___. (10) A. carbohydrates B. carbon dioxide C. carbon monoxide D. chlorophyll E. water

2. _____Hydrolysis of lipid molecules yields ____. (4) A. amino acids and water B. amino acids and glucose C. fatty acids and glycerol D. glucose and glycerol E. glycerol and water

3. ______Enzymes affect biochemical reactions by ___. (6) A. blocking their end product formation B. destroying all substances produced in the reactions C. raising the temperature of the reaction’s environment D. reversing their direction E. accelerating the reaction rates

4. _______The majority of ATP molecules derived from nutrient metabolism are generated by (the) ____. (9) A. anaerobic fermentation and glycolysis B. fermentation and electron transport chain C. glycolysis and substrate phosphorylation D. Krebs cycle and electron transport chain E. Substrate phosphorylation

5. ______The variable portion of a DNA nucleotide is at its ____. (16) A. base B. deoxyribose C. phosphate group

D. ribose

E. sugar

6. ______Which of the following is not a polymer? (4) A. DNA B. glycogen C. glucose

D. RNA

E. starch

7. ______In the electron transport chain, the final electron acceptor is ____. (9) A. oxygen B. water C. cytochrome oxidase D. the mitochondrion E. a hydrogen ion

8. _______All of the following statements about the light reactions of photosynthesis are true, EXCEPT ___. (10) A. carbon dioxide fixation occurs – ie. CO2 is reduced to organic compounds B. light is absorbed by photosystems C. water is split into oxygen, hydrogen ions and electrons D. light reactions consist of cyclic and noncyclic photophosphorylation E. ATP is synthesized

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9. ______The levels of organization of an organism, starting with the most microscopic level, is shown by which of the following sequences? (1) A. cells…organs…chemicals…tissues…systems….organism B. chemicals…cells…tissues…organs…systems…organism C. systems…organs…tissues….cellls…chemicals….organism D. organism… systems…tissues….organs…chemicals…cells E. chemicals…cells…organs…tissues…systems…organism 10. ______All of the following statements about the cell membrane are true, EXCEPT ____. (8) A. it functions as a selective barrier between the intracellular fluid and the extracellular fluid B. the proteins within it are classified as intrinsic (integral) or extrinsic (peripheral) C. the major lipid within it is cholesterol D. the fluid-mosaic model describes the fluidity and mobility of the membrane E. the phospholipids within are amphipathic-that is they each contain polar and nonpolar regions 11. ______In comparing glycolysis under aerobic vs. anaerobic conditions ___. (9) A. pyruvate is converted to lactate under aerobic conditions, while it is converted to acetyl CoA under anaerobic conditions B. pyruvate is converted to acetyl CoA under aerobic conditions, while it is converted to lactate under anaerobic conditions C. oxygen is used in anaerobic glycolysis, while it is not used in aerobic conditions D. humans are only capable of aerobic metabolism E. lactate is converted to pyruvate under aerobic conditions, while the reverse occurs under anaerobic conditions

12. ______The dark reactions of photosynthesis, in which carbon dioxide fixation occurs, are called the ___. (10) A. Krebs cycle B. Calvin cycle C. Cori cycle D. Cyclic AMP cycle E. Carbon cycle 13. _______In comparing photosynthesis to respiration, which of the following statements is true? (10) A. carbohydrates are produced in respiration, but not in photosynthesis B. oxygen is produced in respiration, but not in photosynthesis C. carbon dioxide is produced in photosynthesis, but not in respiration D. water is produced in photosynthesis, but not in respiration E. oxygen is produced in photosynthesis, but not in respiration

14. ______Which of the following processes occurs in both respiration and photosynthesis? (10) A. Calvin cycle B. Chemiosmosis C. Krebs cycle D. Citric acid cycle E. Glycolysis

15. _______Water’s ability to regulate environmental temperatures within a small range conducive to life is partially due to its ___. (3) A. function as a universal solvent B. high heat capacity C. nonpolarity D. viscosity E. maximum density at zero degrees Celsius

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16. _______Regarding mitosis and cytokinesis, one difference between higher plants and animals is that in plants ___. (11) A. the spindles contain cellulose microfibrils in addition to microtubules, whereas animal spindles do not contain microfibrils B. sister chromatids are identical, whereas in animals they differ from one another C. a cell plate begins to form at telophase, whereas in animals a cleavage furrow is initiated at that stage D. chromosomes become attached to the spindle at prophase, whereas in animals chromosomes do not become attached until anaphase E. spindle poles contain centrioles, whereas spindle poles in animals do not

17. ________Which of the following statements is true about the Krebs (citric acid) cycle and the Calvin (lightindependent) cycle? (10) A. they both result in a net production of ATP and NADH B. they both require a net input of ATP C. they both result in a release of oxygen D. they both take place within the cytoplasmic matrix E. they both are carried out by enzymes located within an organelle matrix

18. ______The bonding of two amino acid molecules to form a larger molecule requires ___. (5) A. the release of a water molecule B. the release of a carbon dioxide molecule C. the addition of a nitrogen atom D. the addition of a water molecule E. an increase in activation energy

19. _______When hydrogen ions are pumped out of the mitochondrial matrix, across the inner mitochondrial membrane, and into the space between the inner and outer membranes, the result is ____. (9) A. damage to the mitochondrion B. the reduction of NAD+ C. the restoration of the Na-K balance across the membrane D. the creation of a proton gradient E. the lowering of pH in the mitochondrial matrix

20. _______The function of water in photosynthesis is to ___. (10) A. combine with CO2 B. absorb light energy C. supply electrons in the light-dependent reactions D. transport H+ ions in the light independent (dark) reactions E. provide O2 for the light independent (dark) reactions

Questions #21-24. Choices may be used once, more than once, or not at all. A. Centriole

B. Lysosome

C. Nucleolus

D. Peroxisome

E. Ribosome

21. ______Found in both prokaryotic and eukaryotic cells (7) 22. _______Possesses a microtubular structure (7) 23. _______Assembles ribosomal precursors (7) 24. ________Contains hydrolytic enzymes associated with the intracellular digestion of macromolecules (7)

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25. _______A solution hypotonic relative to a red blood cell ____. (8) A. will cause an immersed red blood cell to burst B. will cause an immersed red blood cell to undergo crenation C. will have no effect on a red blood cell that is immersed in it D. will cause an immersed red blood cell to shrink E. may be a 1% NaCl solution

26. ______Which of the following statements is true? (12) A. in prophase the sister chromatids separate B. in telophase the nuclear membrane begins to form C. in metaphase the sister chromatids begin condensation D. in anaphase the chromosomes move to the equator E. in prophase cytokinesis occurs

27. ______All of the following are carbohydrates except ____. (5) A. starch B. glycogen C. chitin

D. glycerol

E. cellulose

28. ______Which of the following will least affect the effectiveness of an enzyme? (6) A. temperature B. pH C. concentration of substrate D. concentration of enzyme E. original activation energy of the system

29. ______Carbon dioxide enters the plant through the ___. (10) A. stomata B. stroma C. thylakoid membrane

D. bundle sheath cell

30.______ The destruction of which of the following would most cripple a cell’s ability to undergo cell division? (12) A. microfilaments B. intermediate filaments C. microtubules D. actin fibers E. keratin fibers

31.______ Which of the following molecules can give rise to the most ATP? (9) A. NADH B. FADH2 C. pyruvate D. glucose

32. _______ A covalent bond is likely to be polar when ___. (4) A. one of the atoms sharing electrons is much more electronegative than the other atom B. the two atoms sharing electrons are equally electronegative C. the two atoms sharing electrons are of the same element D. it is between two atoms that are both very strong electron acceptors E. it joins a carbon atom to a hydrogen atom

33. _____ What is the value of the alcoholic fermentation pathway? (9) A. it produces ATP B. it produces lactic acid C. it produces ADP for the electron transport chain D. it replenishes carbon dioxide for the dark reaction E. it replenishes NAD+ so that glycolysis can produce ATP

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34. ______ After strenuous exercise, a muscle cell would contain increased amounts of all of the following EXCEPT ___. (9) A. ADP B. CO2 C. lactate D. glucose E. Pi

35. ______ The partial negative charge at one end of a water molecule is attracted to the partial positive charge of another water molecule. What is this attraction called? (3) A. a covalent bond B. a hydrogen bond C. an ionic bond D. a hydrogen shell E. a hydrophobic bond 36.______ Water’s high specific heat is mainly a consequence of the ____. (3) A. small size of the water molecules B. high specific heat of oxygen and hydrogen atoms C. fact that water is a poor heat conductor D. inability of water to dissipate heat into dry air E. absorption and release of heat when hydrogen bonds break and form

37._______ What maintains the secondary structure of a protein? (5) A. peptide bonds B. hydrogen bonds D. ionic bonds E. electrostatic charges

C. disulfide bonds

38. ______ Upon chemical analysis, a particular protein was found to contain 438 amino acids. How many peptide bonds are present in this protein? (5) A. 20 B. 437 C. 438 D. 439 E. 876

39. ______All of the following bases are found in DNA except ___. (16) A. thymine B. adenine C. uracil D. guanine

E. cytosine

40. ______ Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules? (7) A. lipids B. starches C. proteins D. steroids E. glucose

41. _______ What are the membrane structures that function in active transport? (8) A. peripheral proteins B. carbohydrates D. cytoskeleton filaments E. integral proteins

C. cholesterol

42._____ Which of the following would move through the lipid bilayer of plasma membrane most rapidly? (8) A. CO2 B. an amino acid C. glucose D. K+ E. starch

43._______ Amino acids are acids because they possess which functional group? (4) A. amino B. alcohol C. carboxyl D. sulfhydryl

E. aldehyde

44.______ Grana and thylakoids are all structural components found in ___. (7) A. cilia and flagella B. chloroplasts C. mitochondria D. lysosomes E. nuclei

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45. ______In garden peas, a single gene controls stem length. The recessive allele (t) produces short stems when homozygous. The dominant allele (T) produces long stems. A short-stemmed plant is crossed with a heterozygous long-stemmed plant. Which of the following represents the expected phenotypes of the offspring and the ratio in which they will occur? (14) (A) 3 long-stemmed plants: 1 short-stemmed plant (B) 1 long-stemmed plant: 1 short-stemmed plant (C) 1 long-stemmed plant: 3 short-stemmed plants (D) Long-stemmed plants only (E) Short-stemmed plants only

Questions 46-50 refer to the following diagram. Options may be used once, more than once, or not at all.

46. _______A chemical group that, together with a sugar and a nitrogen base, makes up a nucleotide (16) 47. ________A hydrogen bond (16) 48. _______A pyrimidine (16) 49. ________A 5' carbon of deoxyribose (16) 50. ________Most likely to be broken during replication (16)

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Achondroplastic dwarfism is a dominant genetic trait that causes severe malformation of the skeleton. Homozygotes for this condition are spontaneously aborted (hence, the homozygous condition is lethal) but heterozygotes will develop to be dwarfed. Matthew has a family history of the condition, although he does not express the trait. Jane is an achondroplastic dwarf. Matthew and Jane are planning a family of several children and want to know the chances of producing a child with achondroplastic dwarfism. 51. ________The genotypes of Matthew and Jane are best represented as _____. (14) Matthew Jane (A) AA Aa (B) Aa aa (C) aa aa (D) aa Aa (E) Aa Aa 52. ________The probability that Matthew and Jane’s first child will be an achondroplastic dwarf is _____. (14) (A) 0% (B) 25% (C) 50% (D) 75% (E) 100%

53. ______If three children are born to Matthew and Jane, what are the chances that the first two children will not express the trait but that the third child will be an achondroplastic dwarf? (14) (A) 5/8 (B) 4/8 (C) 3/8 (D) 1/8 (E) 1/16 A male fruit fly (Drosophila melanogaster) with red eyes and long wings was mated with a female with purple eyes and vestigial wings. All of the offspring in the F1 generation had red eyes and long wings. These F1 flies were test crossed with purple-eyed, vestigial-winged flies. Their offspring, the F2 generation, appeared as indicated below.

125 124 18 16 283

F2 Generation red eyes, long wings purple eyes, vestigial wings purple eyes, long wings red eyes, vestigial wings Total

54. ______If in the F1 and F2 generations the same characteristics appeared in both males and females, it would be safe to assume that these traits for eye color and wing length ____. (15) (A) are sex-linked (B) vary in dominance according to sex (C) are sex-influenced characteristics (D) are autosomal characteristics (E) follow the Mendelian rule of independent assortment 55. ______In the F2 generation, the results are best explained by the fact that ____. (15) (A) the test cross with the F1 flies resulted in sterile offspring (B) these genes for eye color and wing shape do not pass through the F1 generation (C) these genes for eye color and wing shape are found on the same chromosome (D) crossing-over decreases variability (E) the genes are sex-linked

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56. ______A represents the dominant allele and a represents the recessive allele of a pair. If, in 1,000 offspring, 500 are aa and 500 are of some other genotype, which of the following are most probably the genotypes off the two parents? (14)

A. Aa and Aa B. Aa and aa C. AA and Aa D. AA and aa E. aa and aa 57. ______The nitrogenous base, adenine, is found in which three of the following ___. (5) A. Proteins, chlorophyll, and vitamin A B. Protein, ATP, and DNA C. ATP, DNA, and RNA D. Chlorophyll, ATP, and DNA E. Proteins, carbohydrates, and ATP 58. _____A diploid cell has three pairs of homologous chromosome designated J/J2, K1/K2 and L1/L2. Which of the following represents a probable chromosome complement in a haploid cell formed by meiosis? (13) A. J1 and K1 B. J1 and J2 C. J2, K1, and L2 D. J1, J1, K2, and K2 E. J1, J2, K1, K2, L1, and L2 59. ______If plant cells are immersed in distilled water, the resulting movement of water into cells is called _. (8) A. conduction B. active transport C. transpiration D. osmosis E. facilitated diffusion 60. ______In corn, the trait for tall plants (T) is dominant to the trait for dwarf plants (t) and the trait for colored kernels (C) is dominant to the trait for white kernels (c). In a particular cross of corn plants, the probability of an offspring being tall is 1/2 and the probability of a kernel is being colored 3/4. Which of the following most probably represents the parental genotypes? (14) A. TtCc X ttCc B. TtCc X TtCc C. TtCc X ttcc D. TTCc X ttCc E. TTCc X TtCC

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61. _____ A G protein is inactive when ____. (11) A. GDP displaces GTP B. it is amplified C. GTP is bound to it D. it is phosphorylated by protein kinase E. Ca+2 binds to a G protein linked receptor

62. _____ DAG is produced from _____. (11) A. protein kinase A B. Ca+2

C. PIP2

D. IP3

E. phospholipase C

63 _______Which of these is a logical signal-transduction pathway? (11) A. A tyrosine-kinase receptor activates adenylyl cyclase, which activates phospholipase C, which converts ATP into cyclic AMP, which binds to an intracellular enzyme that carries out a response B. An ion-channel receptor opens, allowing a steroid hormone to enter the cell; the steroid hormone then activates protein kinases that convert GTP to GDP, which binds to an intracellular enzyme that carries out a response. C. An intracellular receptor activates phospholipase C, which cleaves a membrane protein to form IP3, which then activates the opening of an ER channel protein, which releases cyclic AMP into the cytoplasm, where it binds to an intracellular enzyme that carries out a response. D. A G-protein-linked receptor activates G protein, which activates phospholipase C, which cleaves a membrane protein to form IP3, which binds to a calcium channel on the ER, which opens to release calcium ions into the cytoplasm, which bind to an intracellular enzyme that carries out a response

64. ______ If gametes have 8 chromosomes, the cell resulting from syngamy will have ________ chromosomes. (13) A. 8 B. 4 C. 32 D. 16 E. 24

65. _____ Which of the following are mismatched ____. (13) A. haploid-n B. somatic cell – 2n C. zygote-n

D. sperm cell – n

E. gamete - n

66. _____ A molecule that is a second messenger, but not a first messenger is ____. (11) A. cAMP B. insulin C. human growth hormone D. protein kinase E. acetylcholine (neurotransmitter)

67. _____If a cell with 32 chromosomes divides by meiosis, how many chromosomes will each nucleus contain at telophase I? (Assume cytokinesis has occurred.) (13) A. 64 B. 48 C. 32 D. 16 E. 8

68. _______A form of vitamin D-resistant rickets, known as hypophosphatemia, is inherited as an X-linked dominant trait. If a male with hypophosphatemia marries a normal female, which of the following predictions concerning their potential progeny would be true? (15) A. All of their sons would inherit the disease. B. All of their daughters would inherit the disease. C. About 50% of their sons would inherit the disease. D. About 50% of their daughters would inherit the disease. E. None of their daughters would inherit the disease.

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69. ______In DNA replication, DNA polymerase catalyzes the reaction in which ____. (16) A. The double helix unwinds B. The sugar-phosphate bonds of each strand are broken C. A phosphate group is added to the 3’-carbon or 5’-carbon of ribose D. A nucleotide with a base complementary o the base on the template stand is added to the new DNA strand E. The two nucleotide strands come together and intertwine to form a double helix

70. _______The relative location of four genes on a chromosome can be mapped from the following data on crossover frequencies.

Genes B and D C and A A and B C and B C and D

Frequency of crossover 5% 15% 30% 45% 50%

Which of the following represents the relative positions of these four genes on the chromosome? (15) A. ABCD B. ADCB C. CABD D. CBAD E. DBCA

71. _______In fruit flies, vermilion eyes are a sex-linked recessive characteristic. If a vermilion-eyed female is crossed with a wild-type male, what proportion of the male offspring should have vermilion eyes? (15) A. 0% B. 25% C. 50% D. 75% E. 100%

Questions 72-73. Options may be used once, more than once, or not at all. A.Glucose

B. Glycerol

C.

Glycogen

D. Glucagon

E. Guanine

72. _______Essential for the synthesis of neutral fats (5) 73. _______A storage form of carbohydrate in muscle (5)

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Questions 74-76 refer to the diagram of the plasma membrane below. Options may be used once, more than once, or not at all.

74. ________Hydrophilic portion of lipid molecule. (8) 75. _________Cell-recognition component. (8) 76. _________Carriers involved in cell transport. (8)

Questions 77-78. Options may be used once, more than once, or not at all. The illustrations below represent homologous pairs of chromosomes as they appear in various stages of mitosis and meiosis (2n=2).

77. _______At which stage do the chromosomes have the LEAST amount of DNA per cell? (12) 78. ________Which diagram represents anaphase of meiosis I? (13)

Question 79-82 refer to the following pedigree that illustrates the inheritance of sickle cell anemia. Shading indicates the presence of sickle cell anemia.

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79. _______The phenotype of individual C is best explained by the fact that this individual received an allele for sickle cell anemia from (15) A. an autosomal chromosome of each parent B. the Y chromosome contributed by the father C. the X chromosome contributed by the mother D. the X chromosome contributed by the father E. the Y chromosome contributed by the mother 80. ________What is the probability that the next child of parents A and B would have had sickle cell anemia? (15) A. 0% B. 25% C. 60% D. 75% E. 100% 81. _______The most reasonable explanation for the fact that the offspring of C and D do not have sickle cell anemia is that each received a (15) A. sickle allele from the mother B. normal allele from the father C. sickle allele from each parent D. normal allele from each parent E. pair of normal alleles from the father

82. _______Which of the following statements is correct about the four offspring of C an D? (15) A. Only the females are carriers of the sickle cell trait. B. Only the males are carriers of the sickle cell trait. C. Only the females are heterozygous for the sickle cell trait. D. All are homozygous for the sickle cell trait. E. All are carriers of the sickle cell trait.

83. _______In the series of enzyme reactions shown above, product Z is able to occupy the active site of enzyme E2.Product Z can therefore first inhibit the production of ______. (6) (A) W (B) E1 (C) X (D) E2 (E) Y

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A biologist prepares an in vitro analysis of the activity of the enzyme amylase, which promotes the hydrolysis of polysaccharides to monosaccharide residues. Three flasks containing 5 milliliters of 4 percent amylose (starch) in water are prepared with the addition at time zero of each of the substances indicated in the diagrams below.

84. _____In an experiment to test the effect of amylase on starch, the control would be ____. (6) (A) flask A only (B) flask B only (C) flask C only (D) flasks A and B (E) flasks A and C 85. ______After 2 minutes, a positive test for sugar would most likely be observed in ____. (6) (A) flask A only (B) flask B only (C) flask C only (D) flasks A and C (E) flasks Band C 86. ______Support for the hypothesis of enzyme denaturation can be obtained by comparing starch digestion in ___. (6) (A) flasks A and B after 5 minutes (B) flasks Band C after 5 minutes (C) flasks A and C after 5 minutes (D) flask A at time zero and again after 5 minutes (E) flask B at time zero and again after 5 minutes 87. ______In a diploid organism with the genotype AaBBCCDDEE, how many genetically distinct kinds of gametes would be produced? (12) (A) 2 (B) 4 (C) 8 (D) 16 (E) 32 88. _____Crossing-over is a process that involves the _____. (13) (A) exchange of genetic material between chromosomes that are homologous (B) exchange of genetic material between chromosomes that are not homologous (C) random segregation of genes on different chromosomes (D) random segregation of genes on homologous chromosomes (E) continued maintenance of genetic stability

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Use the following key to answer questions 89-92. Options may be used once, more than once, or not at all. A. the statement is true for mitosis only B. the statement is true for meiosis I only C. the statement is true for meiosis II only D. the statement is true for mitosis and meiosis I E. the statement is true for mitosis and meiosis II ______ 89. Diploid cells become haploid cells (13) ______ 90. Sister chromatids are separated from each other (13) ______ 91. Chromosome number remains constant (13) ______ 92. The process(es) is (are) preceded by a copying (replication) of the DNA (13)

93. _____ A saturated suspension of starch is enclosed in a bag formed from dialysis tubing, a material through which water can pass, but starch cannot. The bag with the starch is places into a beaker of distilled water. All of the following are expected to occur EXCEPT: (8) A. there will be a net movement of water from a hypotonic region to a hypertonic region B. there will be a net movement of solute from a hypertonic region to a hypotonic region C. there will be a net movement of water from a region of higher water concentration to a region of lower water concentration D. the dialysis bag with its contents will gain weight E. no starch will be detected outside the dialysis bag

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