1. Which one of the following topics belongs to a different sub-discipline of genetics when compared to the rest?

a. Allele frequencies of certain gene in different environments

b. Mechanism of gene regulation

c. Chemical alternation of chromosomes

d. Mechanism of DNA repairs and maintenance

Correct Answer: a

2. The complete genetic makeup of an organism is referred to as its

a. chromosome

b. alleles

c. phenotype

d. genome

Correct Answer: d

3. The stage of meiosis in which chromosomes pair and cross over is

a. prophase II

b. metaphase II

c. prophase I

d. metaphase I

Correct Answer: c

4. A strand of DNA with the sequence AACTTG will have a complimentary strand with the following sequence





Correct Answer: a

5. Which blood type would not be possible for children of a type AB mother and a type A father?

a. B

b. AB

c. O

d. A

Correct Answer: c

6. Which of the following characteristics made the pea plant Pisum sativum an ideal organism for Mendel’s studies?

a. All of the answers are correct

b. It has the ability to self-fertilize

c. It was easy to cross-fertilize one plant with another

d. It has easily identifiable traits

Correct Answer: a

7. Mutations which occur in body cells which do not go on to form gametes can be classified as

a. somatic mutations

b. auxotrophic mutations

c. morphological mutations

d. oncogenes

Correct Answer: a

8. Cystic fibrosis is

a. Autosomal dominant disorder

b. Sex-linked dominant disorder

c. Sex-linked recessive disorder

d. Autosomal recessive disorder

Correct Answer: d

9. When the activity of one gene is suppressed by the activity of a non-allelic gene, it is known as

a. Hypostasis

b. Complete dominance

c. Co-dominance

d. Epistasis

Correct Answer: d

10. Which of the following factors could lead to variations in the offspring of asexually reproducing organisms?

a. Fertilization

b. Independent assortment

c. Mutations

d. Crossing over

Correct Answer: c

11. Mitotic cell division results in two cells that have

a. 2n chromosomes and are genetically identical

b. n chromosomes and are genetically identical

c. n chromosomes and are genetically different

d. 2n chromosomes and are genetically different

Correct Answer: a

12. A duplication is

a. an exchange between non-homologous chromosomes

b. loss of genes in part of a chromosome

c. an extra set of chromosomes in an organism

d. an extra copy of the genes on part of a chromosome

Correct Answer: d

13. Relative to a cross between a black-bodied male and a wild-type female fruit fly, the cross between a wild-type male and a black-bodied female is called the

a. Reciprocal cross

b. Test cross

c. Sex cross

d. Pleiotropic cross

Correct Answer: a

14. Which component of transcribed RNA in eukaryotes is present in the initial transcript but is

removed before translation occurs

a. 3’ Poly A tail

b. Ribosome binding site

c. 5’ cap

d. Intron

Correct Answer: d

15. Choose the correct statement about the genetic code

a. all of the above

b. includes 61 codons for amino acids and 3 stop codons

c. almost universal

d. three bases per codon

Correct Answer: a

16. A measurable or observable trait or characteristic is called a

a. SNP

b. genome

c. Phenotype

d. Genotype

Correct Answer: c

17. The crossing of F1 to homozygous recessive parent is called

a. Test cross

b. Reciprocal cross

c. F1 cross

d. Back cross

Correct Answer: d

18. Which of the following would be used to determine the probability of three independent events in order?

a. Chi-square test

b. Binomial expansion

c. Product rule

d. Sum rule

Correct Answer: c

19. If a Punnett square is used to visualize a three-factor cross (trihybrid cross) how many boxes would be inside of the square?

a. 64

b. 32

c. 16

d. 24

Correct Answer: a

20. If an individual that phenotypically has dominant traits is mated to another individual that also has  dominant traits and the progeny have both dominant and recessive traits it indicates that

a. Both parents are homozygotic

b. No conclusions can be made about the

genotypes of the parents

c. One parent is heterozygotic and one is homozygotic

d. Both parents are heterozygotic

Correct Answer: d

21. An Hfr strain of E. coli contains

a. a bacterial chromosome with the F factor inserted

b. a bacterial chromosome with a human gene inserted

c. a bacterial chromosome with a phage inserted

d. a human chromosome with a transposable element inserted

Correct Answer: a

22. A true breeding line of green pod pea plants is crossed with a true-breeding line of yellow pod plants.

All of their offspring have green pods. From this information, it can be stated that the green color

is—– to the yellow color

a. Recessive

b. CoDominant

c. Blended

d. Dominant

Correct Answer: d

23. What would be the dimensions of a Punnet square for the cross Ww x ww?

a. 2×2

b. 4×4

c. 2×1

d. 1×1

Correct Answer: a

24. In dihybrid cross, the ratio 9:3:3:1 indicates

a. Codominance

b. Intermediate Dominance

c. Three alleles for each trait

d. Independent assortment

Correct Answer: d

25. What would be the frequency of aabbcc individuals from a mating of two AaBbCc individuals?

a. 1 / 64

b. 1 / 32

c. 1 / 16

d. 1 / 8

Correct Answer: a

26. There are three different genotypes resulting from a monohybrid cross. How many different genotypes would there be resulting from a dihybrid cross?

a. 9

b. 8

c. 16

d. 4

Correct Answer: a

27. 2n+1 in genetics means

a. Trisomy

b. Monosomy

c. Double trisomy

d. Ploidy

Correct Answer: a

28. Drosophila melanogaster used as a model organism and has following pairs of autosomes?

a. Three

b. Four

c. Five

d. Eight

Correct Answer: a

29. If chromosome lacks certain genes, what has most likely occurred?

a. Disjunction

b. Translocation

c. Inversion

d. Deletion

Correct Answer: d

30. The ability of a single gene to have multiple phenotypic effects is

a. Incomplete Dominance

b. Mutliple alleles

c. Pleiotropy

d. Epistasis

Correct Answer: c

31. Two enzymes central to the success of genetic engineering are

a. Restriction Endonuclease and Ligase

b. RNA and DNA polymerase

c. Protease and Lipase

d. Transcriptase and Telomerase

Correct Answer: a

32. The F1 offspring of Mendel’s pea cross always looked like one of the two parental varieties because of the following reason

a. Trait blended together during fertilization

b. No genes interacted to produce parental phenotype

c. One allele was completely dominant over another

d. Each allele affected phenotypic expression

Correct Answer: c

33. One possible result of chromosomal breakage is for a fragment to join a non homologous chromosome. This is called a (an)

a. Translocation

b. Deletion

c. Inversion

d. Duplication

Correct Answer: a

34. In the lysogenic cycle, the DNA of a bacteriophage

a. Goes to host’s ribosomes for translation

b. Degraded by the Host

c. joins bacterial chromosome

d. Attached to inner surface of the host membrane

Correct Answer: c

35. The end result of F factor mediated conjugation

a. convert recipent to F+ and donor to F-

b. both become HFr

c. is that both strains are F+

d. involves transfer of the enitre bacterial chromsome

Correct Answer: c

36. The syndrome in humans in which an individual’s somatic cells contain the three sex chromosomes XXY is called

a. Down’s syndrome

b. Superfemale

c. Klinefelter’s syndrome

d. Turner’s syndrome

Correct Answer: c

37. A cell that contain 2n-1 chromosomes is

a. aneuploid

b. polyploid

c. monosomic

d. trisomic

Correct Answer: c

38. In a cross of round hybrid pea with a true breeding round parent (Ww x WW), what genotypic proportions would be observed in the offspring?

a. All Heterozygous

b. Half round, half wrinkled

c. All homozygous

d. Half Heterozygous, half homozygous

Correct Answer: d

39. Homozygosity and heterozygosity of an individual can be determined by

a. Test cross

b. Self-fertilization

c. Reciprocal cross

d. All of these

Correct Answer: a

40. Starting with a cross between AA and aa, the proportion of heterozygotes in the F2 progeny will be

a. 1 / 2

b. 1 / 8

c. 1 / 4

d. All Heterozygotes

Correct Answer: a

41. A high blood ammonia level occurs in

a. Hurler’s Syndrome

b. Phenylketonuria

c. Ornithine transcarbamylase (OTC) deficiency

d. Galactosemia

Correct Answer: c

42. The risk of abnormality in the child of a mother with untreated phenylketonuria is

a. Almost 100%

b. 0.01

c. 0.1

d. 0.25

Correct Answer: a

43. Familial hypercholesterolemia is caused by mutations in the gene which encoded what

a. High density lipoprotein

b. low density lipoprotein

c. Low density lipoprotein receptor

d. HMG-CoA reductase

Correct Answer: c

44. Tay-Sachs disease is caused by deficiency of

a. Alpha-L-iduronidase

b. Glucose-6-phosphatase

c. Homogentisic acid oxidase

d. Hexosaminidase A

Correct Answer: d

45. The presence of an extra digit is referred to as

a. brachydactyly

b. clinodactyly

c. polydactyly

d. Arachnodactyly

Correct Answer: c

46. If boht parents are affected with the same autosomal recessive disorder then the probability that each of their children will be affected

a. All

b. 1 in 4

c. 1 in 2

d. 2 in 3

Correct Answer: a

47. How many phenotypes can occur in the human blood group ABO with alleles IA IB i?

a. 4

b. 1

c. 3

d. 2

Correct Answer: a

48. In the F1 generation of a monohybrid cross, the phenotypic ratio would be

a. 3:1

b. 1:2:1

c. 2:1:1

d. 1:1:2

Correct Answer: a

49. A pedigree chart shows

a. The pattern of inheritence of a specific gene

b. Which genes are co-dominant

c. The genotypic ratios of the offspring

d. The type of gametes produced by the parents

Correct Answer: a

50. What structure is responsible for moving the chromosomes during mitosis?

a. spindle

b. nuclear membrane

c. cytoplasm

d. nucleolus

Correct Answer: a