Question Bank No: 1

1. Two Genes R and Y are located very close on the chromosomal linkage map of maize plant.When RRYY and rryy genotype are hybridized, the F2segregation will show:

 a)Higher number of the parent types
 b)Higher number of the recombinant types
 c)Segregation in the expected 9:3:3:1 ratio
 d)Segregation in 3 : 1 ratio

2. Sickle cell anemia is

 a)Characterized by elongated sickle like RBCs with a nucleus
 b)An autosomal linked dominant trait
 c)Caused by substitution of valine by glutamic acid in the βglobin chain of haemoglobin
 d)Caused by a change in a single base pair of DNA

3. In Drosophila, the sex is determined by:

 a)The ratio of pairs of X-chromosomes to the pairs of autosomes
 b)X and Y chromosomes
 c)The ratio of number of X- chromosomes to the sets of autosomes
 d)Whether the egg is fertilized or develops parthenogenetically

4. Haemophilia is more commonly seen in human males than in human females because

 a)This disease is due to a Y- linked recessive mutation
 b)This disease is due to a X- linked recessive mutation
 c)This disease is due to a X- linked recessive mutation
 d)A greater proportion of girls die in infancy

5. Excessive growth of hair on the pinna is a feature found only in males because

 a)The gene responsible for the character is recessive in females and dominant only in males
 b)The character is induced in males as males produce testosterone
 c)The female sex hormone estrogen suppresses the character in females
 d)The gene responsible for the character is present on the Y chromosome only

6. A self-fertilizing trihybrid plant forms:

 a)8 different gametes and 32 differernt zygotes
 b)8 different gametes and 16 differernt zygotes
 c)8 different gametes and 64 differernt zygotes
 d)4 different gametes and 16 differernt zygotes

7. A person with unknown blood group under ABO system, has suffered much blood loss in an accident and needs immediate blood transfusion. His one friend who has a valid certificate of his own blood type, offers for blood donation without delay.What would have been the type of blood of the donor friend?

 a)Type A
 b)Type B
 c)Type AB
 d)Type O

8. Aman and a women, who do not show any apparent signs of a certain inherited disease, have seven children (2 daughter and 5 sons). Three of the sons suffer from the given disease but none of the daughters are affected. Which of the following mode of inheritance do you suggest for this disease?

 a)Sex-linked recessive
 b)Autosomal dominant
 c)Sex-limited recessive
 d)Sex-linked dominant

9. Genes for cytoplasmic male sterility in plants are generally located in:

 a)Nuclear-genome
 b)Mitochondrial genome
 c)Chloroplast genome
 d)Cytosol

10. If a colour blind woman marries a normal visioned man, their sons will be

 a)Three-fourths colourblind and one-fourth normal
 b)One-half colourblind and one - half normal
 c)All normal visioned
 d)All colourblind

11. A character which is expressed in a hybrid is called

 a)Dominant
 b)Recessive
 c)Co-dominant
 d)Epistatic

12. Select the correct statement from the ones given below with respect to dihybrid cross

 a)Tightly linked genes on the same chromosome show higher recombinations
 b)Genes far apart on the same chromosome show very few recombinations
 c)Tightly linked genes on the same chromosome show very few recombination
 d)Genes loosely linked on the same chromosome show similar recombinations as the tightly linked ones

13. Which one of the following conditions in humans is correctly matched with its chromosomal abnormality/linkage?

 a)Color blindness -Y-linked
 b)Klinefelter's syndrome - 44 autosomes + XXY
 c)Down syndrome-44 autosomes +XO
 d)Erythroblastosis fetalis - X- linked

14. Test cross is a cross between

 a)Hybrid × Hybrid parent
 b)Hybrid × Recessive parent
 c)Hybrid × Dominant parent
 d)Two distantly related species

15. Which of the following pairs is correctly matched?

 a)Sickle cell anemia - X chomosome
 b)Down's syndrome - 21st chomosome
 c)Haemophilia - Ychomosome
 d)Parkinson's disease - X and Y chomosome

16. ABO blood groups in humans are controlled by the gene 1. It has three alleles-1A,1B and i.Since there are three different alleles,six different genotypes are possible.How many phenotypes can occur?

 a)Two
 b)Three
 c)One
 d)Four

17. What is the composite display (paired and arranged according to size) of all the chromosomes of an organism called?

 a)Linotype
 b)Karyotype
 c)Phenotype
 d)Chromotype

18. Rh factor can produce life-threatening disease

 a)Erythroblastosis fetalis
 b)Turner's Syndrome
 c)AIDS
 d)Sickle cell anemia

19. Point mutation involves

 a)Deletion
 b)Insertion
 c)Change in single base pair
 d)Duplication

20. When the effects of both alleles are equally expressed in the heterozygote which one of the following occurs?

 a)Segregation
 b)Codominance
 c)Pleiotropy
 d)Incomplete domnance

21. The genotype is called a ____ when a person is heterozygous at two different loci.

 a)Trihybrid
 b)Dihybrid
 c)Monohybrid
 d)Mutant

22. An individual who has two different alleles of a gene is called

 a)Allelopathic
 b)Homozygous
 c)Heterozygous
 d)Codominant

23. The exchange of segments of non-sister chromatids between chromosomes of a homologous pair is termed

 a)Transformation
 b)Translocation
 c)Crossing over
 d)Chromosomal aberration

24. Which one of the followings is assigned an uppercase letter?

 a)Superior allele
 b)Dominanat allele
 c)Inferior allele
 d)Mutant allele

25. What is the pattern of inheritance called in which phenotype is influenced by many genes?

 a)Polygenic inheritance
 b)Epistasis
 c)Monohybrid cross
 d)Dihybrid cross

26. The genotype of a plant showing the dominant phenotype can be determined by

 a)Back cross
 b)Test cross
 c)Dihybrid cross
 d)Pedigree analysis

27. Restriction enzymes

 a)Are endonucleases which cleave DNA at specific sites
 b)Make DNA complementary to existing DNA or RNA
 c)Cut or join DNA fragments
 d)Are required in vectorless direct gene transfer

28. Removal and insertion of genes is

 a)Genetic engineering
 b)Biotechnology
 c)Gene therapy
 d)Cytogenetics

29. The first mammal clone 'Dolly' was created by

 a)Gregor Mendel
 b)Thomas King
 c)Robert Briggs
 d)Ian Wilmut

30. Transgenic plants are plants having

 a)No gene
 b)Genes in transposition
 c)Genes have no function to perform
 d)Genes of an other organism

31. VNTR is employed for

 a)Protoplasmic culture
 b)DNA finger printing
 c)Regulation of plant growth hormones
 d)Enhancing photosynthesis in desert plants

32. Endonuclease is employed in

 a)Transcription
 b)Translation
 c)Genetic engineering
 d)DNA replication

33. What is true of plasmids

 a)Found in viruses
 b)Contains genes for vital activities
 c)Part of nuclear chromosome
 d)Widely used in gene transfer

34. Chemical knives/ molecular scissors of DNA are

 a)Endonucleases
 b)Polymerases
 c)Ligases
 d)Transcriptases

35. Bacterial plasmid contains

 a)RNA
 b)RNA + protein
 c)DNA
 d)Photosynthetic structures

36. Which enzyme is useful in genetic engineering

 a)DNA-ase
 b)Amylase
 c)Lipase
 d)Restriction endonuclease

37. The most abundant RNA of cell is

 a)mRNA
 b)tRNA
 c)rRNA
 d)Catalytic RNA

38. Who was awarded Nobel Prize for in vitro synthesis of polyribonucleotides

 a)Kornberg
 b)Tatum
 c)Ochoa
 d)Khorana

39. Wobble hypothesis was proposed by

 a)Holley
 b)Nirenberg
 c)Khorana
 d)Crick

40. The smallest RNA is

 a)mRNA
 b)tRNA
 c)rRNA
 d)None of the above

41. Width between strands of DNA is

 a)34A∘
 b)20 A∘
 c)3.4 A∘
 d)340 A∘

42. Special unwinding enzyme that breaks hydrogen bonds between the two strands of DNA is

 a)Primase
 b)Topoisomerase
 c)DNA polymerase
 d)Helicase

43. Barbora Mc clintock is famous for her work on

 a)Rice
 b)Wheat
 c)Maize
 d)Sugarcane

44. Alkaptonuria is caused by a

 a)X -linked recessive gene
 b)X -linked dominant gene
 c)Recessive autosomal gene
 d)Dominant autosomal gene

45. Translation is formation of

 a)Protein from RNA
 b)DNA over DNA
 c)RNA over DNA
 d)DNA over RNA

46. Which is not component of lac operon

 a)Primer gene
 b)Promotor gene
 c)Structural gene
 d)Regulator gene

47. Types of RNA polymerases operative in eukaryotes are

 a)Four
 b)Three
 c)Two
 d)One

48. DNA replication

 a)Begins at 5′ end of chromosome
 b)Adds nucleotides in 3′→5′ sequence in new chain
 c)Proceeds 5′→3′ in new chain
 d)Both A and B

49. Purines of DNA are

 a)Adenine and cytosine
 b)Adenine and guanine
 c)Thymine and guanine
 d)Adenine and thymine

50. A nonsense /termination codon is

 a)UUU
 b)GCG
 c)UAG/UAA
 d)CCC