Competitive Exams: Zoology MCQs (Practice-Test 56 of 112)

  1. The deletion or insertion of a base pair into the genetic code causes a frame shift mutation unless the number of base pairs deleted or inserted is

    1. one base pair

    2. two base pairs

    3. three base pairs

    4. four base pairs

  2. Match list I with list II and select the. Correct answer:

    List-I List-II
    1. A-T change to G-C

    2. A cridine molecule mimics nucleotide pairs and is inserted between 2 adjacent ones

    3. CH3 is attached to a purine base

    4. Two adjacent thymides of the same strand join covalently

    1. Alkylation

    2. Pyrimidine dimer

    3. Base pair substitution

    4. Transversion

    5. Frame-shirt

    • A
    • B
    • C
    • D
      • 3
      • 2
      • 4
      • 5
      • 5
      • 3
      • 1
      • 2
      • 3
      • 5
      • 1
      • 2
      • 4
      • 5
      • 2
      • 1
  3. The enzymes involved in interconversion of relaxed and supercoiled forms of DNA molecules are called

    1. DNA ligases

    2. topoisomerases

    3. polymerases

    4. exonucleases

  4. Which of the following amino acids has single codon?

    1. Isoleucine

    2. Tryptophan

    3. Valine

    4. Arginine

  5. How many base pairs are present per helical turn in Z-DNA?

    1. 4

    2. 8

    3. 10

    4. 12

  6. DNA foot printing technique is usually used to identify

    1. the sites of DNA where DNA-binding proteins attach

    2. the segment of DNA which code for a specific protein

    3. the binding site of RNA polymerase to its promoter region

    4. the site for termination of transcription processes

  7. Which one of the following functions is performed by the restriction enzyme?

    1. Removing exons from the RNA transcript

    2. Removing introns from the RNA trascript

    3. Cutting up foreign DNA

    4. Removing methyl groups from DNA

  8. Which one of the following describes a cosmid?

    1. A plasmid in which cos sites of A phage have been integrated

    2. A cohesive oxidation status of a lysosome in the middle of its hydrylytic action

    3. A segment which is common in all plasmids

    4. The? phage has been integrated to

    PUC 18

  9. How dosage compensation is achieved in Drosophila?

    1. One of the X chromosomes in females is inactivated

    2. The activity of the single Xchromosome in males is upregulated

    3. The activity of the two Xchromosomes in females is downregulated

    4. The activity of the antosomes in females is downregulated

  10. Cystic fibrosis, a disease, develops in people who inherit two copies of a recessive allele. If a man with cystic fibrosis marries a woman without the disease, and for whom there is no family history of the disease, what is the probability that their child will be a carrier?

    1. 0.25

    2. 0.50

    3. 0.75

    4. 1.00

  11. Pre-messenger RNA (pre-mRNA) must be modified before translation because

    1. pre-mRNA contained leader sequence

    2. pre-mRNA contained the non-coding sequences (intron) within the coding region

    3. pre-mRNA contained methylated G nucleotide

    4. pre-mRNA are longer than the gene

  12. Where is the enzyme that catalyzes peptide bonding located?

    1. Larger sub unit of the ribosome

    2. Smaller sub unit of the ribosome

    3. Leader region of the mRNA

    4. tRNA

  13. Which one of the following is the first event in eukaryotic translation process during the binding of. The mRNA leader sequences?

    1. The binding of the mRNA leader to the smaller ribosomal sub unit

    2. The binding of the mRNA leader to the larger ribosomal sub unit

    3. The binding of mRNA leader to the polysomal core

    4. The binding of the mRNA leader to the tRNA

  14. For the production of monoclonal antibody, which one of the following cell lines is used?

    1. Chinese hamster ovary (CHO) cells

    2. Myeloma cells

    3. HeLa cells

    4. Fibroblast cells

  15. Large sub unit of eukaryotic ribosomes consists of

    1. 23S rRNA + 5.8S rRNA + 33 proteins

    2. 28S rRNA + 18S rRNA + 41 proteins

    3. 28S rRNA + 5.8S rRNA + 5S rRNA + 49 proteins

    4. 23S rRNA + 5S rRNA. + 4.5S rRNA + 33 proteins