Biology Today — May 2017

(WallPaper) #1

  1. Which of the following options correctly mentions mustard
    family and its characteristics?
    (a) Brassicaceae – tetramerous flowers, six stamens,
    bicarpellary gynoecium, siliqua type fruit
    (b) Brassicaceae – pentamerous flowers, many stamens,
    pentacarpellary gynoecium, capsule type fruit
    (c) Solanaceae - pentamerous flowers, five stamens,
    bicarpellary gynoecium, berry type fruit
    (d) Poaceae – trimerous flowers, three stamens,
    monocarpellary gynoecium, caryopsis type of fruit

  2. In spermatogenesis, reduction division of chromosome
    occurs during conversion of
    (a) spermatogonia to primary spermatocytes
    (b) primary spermatocytes to secondary spermatocytes
    (c) secondary spermatocytes to spermatids
    (d) spermatids to sperms.

  3. The major limiting factors of an animal population, food and
    space operate through which of the following determinants
    to bring about comparative stability of the population?
    (a) Natality
    (b) Immigration
    (c) Emigration and mortality
    (d) All of these

  4. Which one is mismatched?
    (a) Hydra vulgaris - sea water
    (b) Hydra gangetica - fresh water
    (c) Obelia - sea water
    (d) Physalia - sea water

  5. Chiasmata are most appropriately observed in meiosis during
    (a) diakinesis (b) diplotene
    (c) metaphase-II (d) pachytene.

  6. Which of the following synthetic growth regulators is used
    to promote flowering in pineapple?
    (a) Indolebutyric acid
    (b) Phenylmercuric acetate
    (c) Benzyl aminopurine
    (d) 2-chloroethylphosphonic acid

  7. A person saw a snake in his room when he opened the
    door. Which one of the following is likely to happen in his
    neuro-hormonal control system?
    (a) Sympathetic nervous system is activated releasing
    epinephrine and norepinephrine from adrenal medulla.
    (b) Sympathetic nervous system is activated releasing
    epinephrine and norepinephrine from adrenal cortex.
    (c) Hypothalamus activates the parasympathetic division
    of brain.
    (d) Neurotransmitters diffuse rapidly across the cleft and
    transmit a nerve impulse.
    31. Keystone species deserve protection because these
    (a) are capable of surviving in harsh environmental conditions
    (b) indicate presence of certain minerals in the soil
    (c) have become rare due to overexploitation
    (d) play an important role in supporting other species.
    32. The function of leghaemoglobin, during biological nitrogen
    fixation in root nodules of legumes, is to
    (a) convert atmospheric N 2 to NH 3
    (b) convert ammonia to nitrite
    (c) transport oxygen for activity of nitrogenase
    (d) protect nitrogenase from oxygen.
    33. Red snow is caused by which of the following in alpine
    vegetation?
    (a) Oscillatoria
    (b) Chlamydomonas
    (c) Batrachospermum
    (d) Sargassum
    34. What will happen if the secretion of parietal cells of gastric
    glands is inhibited?
    (a) In the absence of HCl secretion, inactive pepsinogen
    is not converted into the active enzyme pepsin.
    (b) Gastric juice will be deficient in gastric amylase.
    (c) Enterokinase will not be released from the duodenal
    mucosa so, trypsinogen is not converted to trypsin.
    (d) Gastric juice will be deficient in pepsinogen.
    35. A female delivers a baby suffering from stunted growth,
    mental retardation, low intelligence quotient and reduced
    metabolic rate. This is the result of
    (a) hyposecretion of growth hormone
    (b) hypersecretion of pituitrin
    (c) deficiency of iodine in diet
    (d) cancer of the adrenal gland.
    36. A common characteristic for both bacterial and fungal cell
    wall structure is
    (a) it is made of cellulose
    (b) it has mucopeptide
    (c) it is made up of N-acetylglucosamine
    (d) it has lipid bilayer.
    37. During an injury, nasal septum gets damaged and for its
    recovery the cartilage preferred is
    (a) elastic cartilage (b) hyaline cartilage
    (c) calcified cartilage (d) fibrous cartilage.
    38. In photorespiration, glycine enters from
    (a) chloroplast to mitochondrion
    (b) peroxisome to mitochondrion
    (c) mitochondrion to peroxisome
    (d) chloroplast to peroxisome.

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