Competitive Exams: Zoology MCQs (Practice-Test 31 of 112)

  1. Consider the following statements:

    1. In the secondary structure of proteins, the amino acid units are linked by means of phosphodiester bonds.

    2. The tertiary structure of proteins is maintained by weak hydrogen bonds and electrostatic forces.

    Which of the statements given above is/are correct?

    1. 1 only

    2. 2 only

    3. Both 1 and 2

    4. Neither 1 nor 2

  2. Consider the following:

    1. Calcium

    2. Inositol 1, 4, 5-triphosphate

    3. cAMP

    Which of the above is/are second messengers?

    1. 1 only

    2. 2 and 3 only

    3. 1 and 3 only

    4. 1, 2 and 3

  3. In India, Environment (Protection) Act was enacted in which year?

    1. 1966

    2. 1976

    3. 1986

    4. 1996

  4. What is the rate of storage of organic matter in plant tissue in excess of respiratory utilization by the plants during the period of measurement called?

    1. Secondary productivity

    2. Net community productivity

    3. Gross primary productivity

    4. Net primary productivity

  5. Which is the earliest human-like primate and oldest of human ancestors that is considered as on direct line of human evolution?

    1. Propliopithecus

    2. Dryopithecus

    3. Oreopithecus

    4. Ramapithecus

  6. The possession of two pairs of limbs by modem birds as those possessed by amphibians fit in which category?

    1. Plesiomorphic character

    2. Synapomorphic character

    3. Vestigial, character

    4. Acquired character

  7. With reference to ecological niche, consider the following. Statements:

    1. Often, within the same species, different stages in the organism's life history occupy different niches.

    2. In some species, niche segregation may occur between sexes.

    3. When niches of two species overlap, it always results in the elimination of one species.

    Which of the statements given above is/are correct?

    1. 1 and 2 only

    2. 1 and 3 only

    3. 2 only

    4. 1, 2 and 3

  8. What is the form of chromosomal aberration that leads to the fusion of two formerly separate non-homologous chromosomes into a single chromosome, or to the separation of formerly joined sections of a single chromosome into two chromosomes?

    1. Reciprocal translocation

    2. Isochromosome

    3. Robertsonian translocation

    4. Centromeric fusion

  9. Penicillin acts as an antibiotic in susceptible bacteria by interfering with which one of the following?

    1. Protein synthesis

    2. Cell wall formation

    3. The electron transport chain

    4. DNA synthesis

  10. A polypeptide has the following amino acid sequence Met-Ser-Pro-Arg-Leu-Glu-Gly In a mutant the amino acid sequence of this polypeptide was found to be Met-Ser-Ser-Arg-Leu-Glu-Gly What is the type of mutation that occurred in the reading frame of its DNA?

    1. Silent mutation

    2. Nonsense mutation

    3. Mis-sense mutation

    4. Frame-shift mutation

  11. What are the two major features of chromosomes upon which their cytological identification depends?

    1. Length of chromosome and position of centromere

    2. Amount of DNA and intensity of staining

    3. Number of nucleoli and centromeres

    4. Chromosome thickness and length

  12. Two strands of a double helix model of DNA are held together by hydrogen bonds between

    1. Sugar and phosphate group

    2. Sugar and nitrogenous bases

    3. Phosphate groups and nitrogenous bases

    4. Nitrogenous bases

  13. Consider the following pairs:

      • Acridine compounds
      • Frame-shift
      • Mutation
      • Ultraviolet light
      • Conversion of one base into another
      • Bromouracil
      • Thymidine dimer

    Which of the above pairs is/are correctly matched?

    1. 1 only

    2. 1 and 3

    3. 1 and 3

    4. 2 and 3

  14. In birds and moths, the females are characterized by which the following?

    1. Homogametic sex

    2. Heterogametic sex

    3. Solitary sex chromosomes

    4. Haplodiploidy

  15. Which one among the following RNA viruses carries oncogenes?

    1. Hepatitis B virus

    2. Human papilloma virus

    3. Adenovirus

    4. Rous sarcoma virus