BIO 2220 Mendelian Genetics and Cell Replication Transcription Translation Questions
I.Multiple Choice. For each of the following questions, choose the single best answer.
1.The phenotypic ratio in the second generation of offspring of a monohybrid cross is
a. 1:1; b. 2:1; c. 9:3:3:1; d. 1:2:1; e. 3:1
2. The law of segregation
a. Deals with the alleles governing two different traits; b. applies only to linked genes; c. applies only to sex-linked genes; d. explains the behavior of a pair of alleles during meiosis; e. none of these
3. This enzyme catalyzes peptide bond formation during translation:
a. DNA polymerase; b. RNA polymerase; c. DNA primase; d. peptidyl transferase; e. DNA ligase
4. According to Mendel, what kind of gene “disappears” in first-generation offspring pea plants?
a. sex-linked; b. dominant; c. recessive; d. codominant; e. lethal
5. Mendel’s law of independent assortment states that
a. one allele is always dominant to another; b. hereditary units from the male and female parents are blended in the offspring; c. the two hereditary units that influence a certain trait segregate during gamete formation; d. each hereditary unit is inherited separately from the other hereditary units; e. all of these
6. Four of the five answers listed below describe the heterozygous condition. Select the exception.
a. carrier; b. true-breeding; c. heterozygotes; d. hybrid; e. Aa
7. Which of the following is not an autosomal dominant genetic disorder?
a. achondroplasia; b. cystic fibrosis; c. Huntington disease; d. one form of Alzheimer’s disease; e. a, b, and c are all autosomal dominant genetic disorders
8. Phenylketonuria (PKU) can be largely minimized or suppressed by modifying the diet to exclude proteins containing phenylalanine.
a. True; b. False
9. Nucleic acid contains
a. sulfur; b. phosphorus; c. potassium; d. iron; e. manganese
10. In the bonding of nitrogenous bases,
a. adenine is paired with cytosine; b. adenine is paired with guanine; c. cytosine is paired with thymine; d. guanine is paired with cytosine; e. guanine is paired with thymine
11. A nucleotide may contain a
a. purine; b. five-carbon sugar; c. phosphate group; d. pyrimidine; e. all of these
12. Replication of DNA
a. produces RNA molecules; b. produces only new DNA; c. produces two molecules, each of which is half-new and half-old DNA joined lengthwise to each other; d. generates excessive DNA, which eventually causes the nucleus to divide; e. is too complex to characterize
13. DNA ligase
a. fills tiny gaps between short stretches of DNA; b. is involved in crossing over;
b. catalyzes the addition of new DNA nucleotides; d. breaks hydrogen bonds between the two strands of DNA; e. none of the above
14. Having hitchhiker’s thumb is a dominant trait.
a. True; b. False
15. Having a straight hairline is recessive.
a. True; b. False
16. This sex-linked recessive disorder can be successfully treated so that patients can live relatively normal lives.
a. Duchenne muscular dystrophy; b. red-green color blindness; c. PKU (phenylketonuria); d. hemophilia; e. none of the above
17. Translation only occurs during S of interphase.
a. True; b. False
18. In transcription, this nitrogenous base that is not used in replication is used:
a. adenine; b. guanine; c. thymine; d. cytosine; e. uracil
19. Sex-linked traits are most commonly seen in females.
a. True; b. False
20. The anticodon is on this molecule:
a. DNA; b. mRNA; c. tRNA; d. rRNA; e. polypeptide
21. This number of codons in the genetic code of all living things directly codes for amino acids:
a. 20; b. 40; c. 60; d. 61; e. 64
22. Introns are coding sequences on mRNA.
a. True; b. False
23. Where is the first amino acid initially in a growing polypeptide chain relative to the ribosome?
a. E site; b. P site; c. A site; d. small subunit; e. none of the above
24. Peptide bond formation occurs at this location on the ribosome:
a. exit site; b. peptidyl site; c. aminoacyl site; d. small subunit; e. initiation codon
25. Autosomal dominant disorders are the most common genetic disorders in the general human population.
a. True; b. False
26. Promoters are nucleotide sequences on rRNA that carry amino acids.
a. True; b. False
27. In a DNA molecule, hydrogen bonds link together:
a. a sugar and a phosphate; b. pairs of sugars; c. a purine and a pyrimidine; d. two purines; e. two pyrimidines
28. If the sequence of nitrogenous bases in one strand of a DNA molecule is (in the 5’ to 3’ direction) ACTGAGCAT, then the sequence of bases in the complementary strand is:
a. ACTGAGCAT; b. CAGTCTACG; c. GTCAGATGC; d. ACGTATCAG; e. TGACTCGTA
29. Which of the following statements on the replication of DNA is NOT correct?
a. The double helix is opened by enzymes called helicases; b. DNA polymerase catalyzes the synthesis of new DNA strands only in a 3’ to 5’ direction; c. In the leading strand, DNA is synthesized continuously; d. Localized regions of replication are called DNA replication forks; e. Okazaki fragments are synthesized and then joined to form the lagging strand.
30. What is meant by the term “primary transcript”?
a. a gene in a DNA molecule; b. a tRNA molecule; c. an mRNA molecule containing exons only; d. an mRNA molecule containing introns only; e. an mRNA molecule containing both introns and exons
31. Along with RNA splicing, the ________________ are removed.
a. Okazaki fragments; b. anticodons; c. introns; d. exons; e. lagging strands
32. When one strand of a DNA double helix with the base sequence GAGTACACT is transcribed into a strand of RNA, what is the sequence of bases in that RNA strand?
a. GAGTACACT; b. CTCATGTGA; c. CUCAUGUGA; d. AGACGUGUC;
e. TGTCGAGAC
33. In the genetic code, how many bases code for a single amino acid?
a. 20; b. 10; c. 4; d. 3; e. 1
34. Which of the following is not a correct description of initiator tRNA?
a. It is linked to an amino acid; b. It binds to the initiation codon of the mRNA; c. It occupies the A site on the ribosome; d. It is the first tRNA to bind during the translation process; e. It forms part of the initiation complex.
35. True or False. In the genetic code, some amino acids are specified by more than one codon.
a. True; b. False
36. A monohybrid cross is
a. the second generation of a self-fertilized plant; b. a breeding experiment in which the parental varieties have only one trait in common; c. a breeding experiment in which the parental varieties differ in only one trait; d. a triploid plant that results from breeding two very different plants; e. none of the choices are correct.
37. Research since Mendel’s time has established that the law of segregation of genes
a. applies to all forms of life; b. applies to all sexually reproducing organisms; c. applies to all asexually reproducing organisms; d. applies only to unicellular organisms; e. is invalid.
38. Which one of the following is false?
a. The genetic makeup of an organism constitutes its genotype; b. An organism with two different alleles for a single trait is said to be heterozygous; c. Alleles are alternate forms of a gene; d. An allele that is fully expressed is referred to as recessive; e. The expressed physical traits of an organism are called its phenotype.
BIO 2220 Mendelian Genetics and Cell Replication Transcription Translation Questions
39. Alleles of a gene are found at ____________ chromosomes.
a. the same locus on heterologous; b. different loci on homologous; c. different loci on heterologous; d. the same locus on homologous; e. none of the above
40. The phenotypic ratio resulting from a dihybrid cross during independent assortment in the second generation of offspring is expected to be
a. 1:2:1; b. 3:1; c. 9:1:1:3; d. 3:9:9:1; e. 9:3:3:1
41. A carrier of a genetic disorder who does not show symptoms is most likely to be
_____________ to transmit it to offspring.
a.heterozygous for the trait and able; b. heterozygous for the trait and unable; c. homozygous for the trait and able; d. homozygous for the trait and unable; e. none of the above
42. True or False. Gene therapy is successfully used along with the use of stem cells and chemotherapy to treat sickle-cell disease.
a. True; b. False
43. Individual features of all organisms are the result of
a. genetics; b. the environment; c. genetics and cytoplasmic determinants; d. the environment and individual needs; e. genetics and the environment
44. True or False. Having freckles is a recessive condition.
a. True; b. False
45. True or False. Women must be homozygous to show sex-linked conditions.
a. True; b. False
46. Which of the following is an autosomal dominant disorder?
a. phenylketonuria; b. cystic fibrosis; c. Huntington disease; d. hemophilia; e. muscular dystrophy
47. Which of the following involves an allele with a resistance to malaria?
a. hemophilia; b. Tay-Sachs disease; c. dwarfism; d. sickle-cell disease; e. none of the above
48. True or False. Injections and oral medications provide the corrected gene for hemophilia.
a. True; b. False
49. Which of the following genotypes show dominant phenotypes?
a. aa; b. Aa; c. AA; d. Aa and AA; e. AA and aa
50. True or False. Regular exercise on stationary bicycles significantly reduces tremors experienced by individuals with Parkinson’s disease.
a. True; b. False
51. A woman of average height mated with a man with achondroplasia whose father was of average height. What is the chance that this mating will produce offspring with achondroplasia?
a. 0 percent; b. 25 percent; c. 50 percent; d. 75 percent; e. 100 percent
52. If a daughter expresses an X-linked recessive gene, she inherited the trait from
a. her mother; b. her father; c. both parents; d. neither parent; e. her grandmother
53. A spliceosome is a form of which of the following?
a. mRNA; b. tRNA; c. rRNA; d. snRNA; e. none of the above
54. Adenine and guanine are
a. double-ringed purines; b. single-ringed purines; c. double-ringed pyrimidines;
d. single-ringed pyrimidines; e. amino acids
55. In DNA, complementary base pairing occurs between
a. cytosine and uracil; b. adenine and guanine; c. adenine and uracil; d. adenine and thymine; e. all of these
56. Each DNA strand has a “backbone” (or “railing” that consists of alternating
a. purines and pyrimidines; b. nitrogen-containing bases; c. hydrogen bonds; d. sugar and phosphate molecules; e. amines and purines
57. The best adjective used to describe DNA replication is
a. nondisruptive; b. semiconservative; c. progressive; d. conservative; e. lytic
58. The RNA molecule is made up of how many strands?
a. 1; b. 2; c. 3; d. 6; e. 12
59. Which of the following has two important binding sites?
a. mRNA; b. tRNA; c. rRNA; d. snRNA; e. all of these
60. The synthesis of an RNA molecule from a DNA template strand is
a. replication; b. translation; c. transcription; d. DNA synthesis; e. metabolism
61. Amino acids are linked together in proteins by
a. hydrogen bonds; b. peptide bonds; c. anticodons; d. wobble effects; e. codon bonds
62. Ribosomes function as
a. a single unit; b. two-part units; c. three-part units; d. four-part units; e. a multidivisional unit
63. The monomers of DNA and RNA are
a. amino acids; b. monosaccharides; c. nucleotides; d. fatty acids; e. nucleic acids
64. Which one of the following is false?
a. RNA uses the nitrogenous base uracil; b. RNA is a nucleic acid; c. One RNA molecule can include four different nucleotides in its structure; d. RNA molecules have sugar-phosphate; e. RNA uses a sugar with six carbon atoms
65. The synthesis of protein is
a. replication; b. transcription; c. translation; d. duplication; e. none of the above
66. True or False. The genetic code is degenerate.
a. True; b. False
67. True or False. Replication occurs as often as both transcription and translation in the cell cycle.
a. True; b. False
68. Which of the following is involved in taking out introns in eukaryotic cells?
a. RNA polymerase; b. RNA ligase; c. ribozymes; d. tRNA; e. none of the above
69. The signal that marks the end of a gene and causes transcription to stop is
a. RNA polymerase; b. RNA ligase; c. a terminator; d. ribozyme; e. none of the above
70. True or False. The leading strand of DNA uses DNA ligase.
a. True; b. False
71. True or False. The lagging strand of DNA uses DNA polymerase.
a. True; b. False
72. We would expect that a 15-nucleotide sequence will direct the production of a polypeptide that consists of
a. 2 amino acids; b. 3 amino acids; c. 5 amino acids; d. 7 amino acids; e. 15 amino acids
73. True or False. Albinism is an autosomal dominant disorder.
a. True; b. False
74. True or False. All of the initially-made mRNA in prokaryotes is used to code for amino acids.
a. True; b. False
75. Cystic fibrosis (CF) is caused by an allele. A child has CF, even though neither of his parents has CF. This couple also has a child who does not have CF. What is the probability that the non-CF child is heterozygous?
a. 2/3; b. 1/3; c. 2/4; d. ¾; e. ¼
