Competitive Exams: Zoology MCQs (Practice-Test 66 of 112)

  1. Cyanide is a metabolic poison as it

    1. Inhibits the enzymes of TCA cycle

    2. Inhibits the enzyme cytochrome oxidase and blocks tissue respiration

    3. Inhibits glycolysis

    4. Stops protein synthesis

  2. An amino acid has two pKa values 2.3 and 9.3, then its pI is

    1. Zero

    2. 2.3

    3. 5.8

    4. 9.3

  3. Match List I (Secretion) with List H (pH value) and select the correct, answer using the codes given below the lists:

    List-I List-II
    1. Bile

    2. Saliva

    3. Gastric juice

    4. Pancreatic juice

    1. 1.5 to 1.8

    2. 8.0

    3. 7.8 to 8.6

    4. 6.4 to 6.8

    • A
    • B
    • C
    • D
      • 3
      • 4
      • 1
      • 2
      • 3
      • 4
      • 2
      • 1
      • 4
      • 3
      • 1
      • 2
      • 4
      • 3
      • 2
      • 1
  4. Match List I (A part of the nephron) with List II (Function) and select the correct answer using the codes given below the lists:

    List-I List-II
    1. Ascending loop of Henle

    2. Descending loop of Henle

    3. Proximal tubule

    4. Collecting Duct

    1. Reabsorption of glucose

    2. Electrolytes are actively thrown out

    3. Diffusion of water

    4. Passive entry of sodium

    5. Sodium is actively thrown out

    • A
    • B
    • C
    • D
      • 5
      • 4
      • 1
      • 3
      • 2
      • 4
      • 5
      • 1
      • 5
      • 3
      • 2
      • 4
      • 4
      • 5
      • 3
      • 1
  5. Which one of the following causes stiffness of muscles during rigor mortis?

    1. Degeneration of troponin and tropomyosin present in the thin filaments of the muscles.

    2. Breakdown of actin-myosm linkages formed during muscle contraction.

    3. Absence of calcium ions from the myofibrils prior to death.

    4. Exhaustion in the supply of AT? to the muscles of the after death

  6. After fertilization, the vitelline membrane gets separated from the plasma membrane. This is

    1. To prevent polyspermy

    2. To facilitate cleavage

    3. To maintain osmotic tension

    4. For free cell movement during gastrulating

  7. Lamp brush configuration of the chromosomes is found during

    1. Meiosis of female gamete of frog

    2. , mitosis of female somatic cells of frog

    3. Meiosis of male gamete of frog

    4. Meiosis of female gamete of a mammal

  8. The type of parthenogenesis in which the male develops from unfertilized egg and the female from fertilized egg is known as

    1. Thelytoky

    2. Arrhenotoky

    3. Gynogenesis

    4. Apospory

  9. In the unfertilized egg, inactivated NAD kinase is made active only

    1. When cap citation and contact between the gametes have been established

    2. After the penetration of the sperm head, into the vicinity of the egg plasma membrane

    3. When the second polar body of the egg has been discharged

    4. When the amphimixis is over

  10. The first cleavage in chick embryo appears in surface view as a narrow furrow, extending across the central part of the blast disc

    1. Immediately after fertilization

    2. About 3 hours after fertilization

    3. At, 6 hours

    4. At 8 hours

    • Assertion (A): Haemocoelomic fluid of leech has a red colou.
    • Reason (R): The coelomic fluid of leech contains floating red blood corpuscles.
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

    • Assertion (A): The conjugation of Paramecium involves meiosis and fusion of pronuclei of two individual.
    • Reason (R): During the process of conjugation, the macronucleus gradually elongates and later breaks up into fragments which are absorbed into the cytoplasm
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

    • Assertion (A): Fasciola hepatica is hermaphrodite with complex male and female reproductive system.
    • Reason (R): The life cycle of Fasciola hepatica is said to be digenetic and gives two-fold benefit to the worm
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

    • Assertion (A): The birds have large, light spongy bones with ait sac.
    • Reason (R): These adaptations help them during flight
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

    • Assertion (A): Hypertonic solutions increase the viscosity of the cytoplas.
    • Reason (R): Hypertonic solutions decrease the distance between the colloidal particles
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true