53. In a laboratory, a scientist feeds yeast cells sugar made with radioactive carbon and keeps oxygen gas out of the container. In which substance will the radioactive carbon appear first?
(A) water
(B) phospholipids
(C) pyruvate
(D) carbon dioxide
(E) electron transport molecules

49. A peak in_triggers ovulation on about the_day of the monthly cycle. [ (A) progesterone ... fourteenth (B) LH ... seventh (C) FSH ... second (D) LH .. .fourteenth | (E) estrogen ... twentieth

50. Mitosis and cytokinesis result in the formation of_, meiosis and cytokinesis result in the formation of_. (A) 4 diploid cells ... 4 haploid cells (B) 2 diploid cells …2 hap]oid cells (C) 2 diploid cells ... 4 haploid cells | (D) 2 diploid cells ...2 diploid cells (E) 4 haploid cells ...2 diploid cells |：

51. During the early development of a human embryo the_________eventually forms_________. (A) blastocoel ... arch enter on (B) epiblast...ectodermal, mesodermal, and endodermal tissues (C) epiblast... placenta (D) trophoblast... embryo proper (E) hypoblast ... amniotic cavity

52. You would expect a cell with an extensive Golgi apparatus to (A) make a lot of ATP (B) secrete a lot of material (C) move actively (D) perform photosynthesis (E) store large quantities of food

54. Which of the following people would probably be making the most antidiuretic hormone?   (A) a person drinking beer (B) a person swimming in a cold lake (C) a person eating salty potato chips (D) a person drinking acidic lemonade (E) none of the above - the production of anti diuretic hormone is constant 

55. The brain perceives the brightness of light by sensing (A) the voltage of action potentials in the optic nerve (B) the frequency of action potentials in the optic nerve (C) which specific rod cells are stimulated (D) how many hair cells are stimulated (E) action potentials from brightness-sensing neurons

56. In what symptoms may be resulted by damage to the corpus callosum? (A) loss of short-term memory (B) inability to integrate information from the two sides of the body (C) inability to form long-term memory (D) sleeplessness (E) loss of fine motor control

57. What does the Hardy-Weinberg expression 2pq represent? (A) the gene frequency of the dominant allele (B) the gene frequency of the recessive allele (C) the frequency of the dominant phenotype (D) the frequency of the recessive phenotype (E) the frequency of heterozygotes

58. Which developmental sequence is correct? (A) fertilization→gastrulation→blastula formation→morula formation→cleavage (B) cleavage→fertilization→blastula formation→momla formation→gastmlation (C) fertilization→cleavage→blastula formation→morula formation→gastralation (D) fertilization→cleavage→morula formation—blastula formation→gastrulation (E) fertilization→cleavage→momla formation→gastmlation→blastula formation .

59. Which of the following best represents the path of a signal that causes muscle contraction? (A) motor neuron→sarcoplasmic reticulum→sarcolemma→transverse tubules (B) transverse tubules→sarcoplasmic reticulum→sarcolemma→motor neuron (C) motor neuron→transverse tubules→sarcolemma→sarcoplasmic reticulum (D) sarcoplasmic reticulum→transverse tubules→sarcolemma→motor neuron (E) motor neuron→sarcolemma→transverse tubules→sarcoplasmic reticulum