NEET-XII-Physics

Previous Year Paper year:2017

with Solutions -
 
  • Qstn #136
    Which of the statements given below is not
    true about formation of Annual Rings in trees?
    (1) Annual ring is a combination of spring
    wood and autumn wood produced in a year.
    (2) Differential activity of cambium causes
    light and dark bands of tissue early and
    late wood respectively.
    (3) Activity of cambium depends upon
    variation in climate.
    (4) Annual rings are not prominent in trees of
    temperate region.
    digAnsr:   4
    Ans : (4)
    Sol. Growth rings are formed by the seasonal
    activity of cambium. In plants of temperate
    regions, cambium is more active in spring and
    less active in autumn seasons. In temperate
    regions climatic conditions are not uniform
    throughout the year. However in tropics
    climatic conditions are uniform throughout
    the year.
  • Qstn #137
    Which of the following ecological pyramids is
    generally inverted?
    (1) Pyramid of numbers in grassland
    (2) Pyramid of energy
    (3) Pyramid of biomass in a forest
    (4) Pyramid of biomass in a sea
    digAnsr:   4
    Ans : ( 4 )
    Sol. In an aquatic ecosystem, the pyramid of
    biomass is generally inverted.
    TC = Large fishes
    SC = Small fishes
    PC = Zooplanktons
    PP = Phytoplanktons
  • Qstn #138
    Placentation in which ovules develop on the
    inner wall of the ovary or in peripheral part, is
    (1) Basal
    (2) Axile
    (3) Parietal
    (4) Free central
    digAnsr:   3
    Ans : ( 3 )
    Sol. In parietal placentation the ovules develop on
    the inner wall of ovary or in peripheral part.
    eg. Mustard, Argemone etc.
    30
  • Qstn #139
    Which of the following protocols did aim for
    reducing emission of chlorofluorocarbons into
    the atmosphere?
    (1) Montreal Protocol
    (2) Kyoto Protocol
    (3) Gothenburg Protocol
    (4) Geneva Protocol
    digAnsr:   1
    Ans : ( 1 )
    Sol. To control the deleterious effect of the
    stratospheric ozone depletion an
    international treaty was signed at Montreal,
    Canada in 1987. It is popularly known as
    Montreal protocol.
  • Qstn #140
    Which of the following contraceptive methods
    do involve a role of hormone?
    (1) Lactational amenorrhea, Pills Emergency
    contraceptives.
    (2) Barrier method, Lactational amenorrhea,
    Pills.
    (3) CuT, Pills, Emergency contraceptives.
    (4) Pills, Emergency contraceptives, Barrier
    methods.
    digAnsr:   1
    Ans : ( 1 )
    Sol. ï‚® In lactational amenorrhoea, due to high
    prolactin level, gonadotropin level
    decreases.
    ï‚® Oral pills are either progestogens or
    progestogen-estrogen combinations used
    by the females.
    ï‚® Emergency contraceptives includes the
    administration of progestogens or
    progestogen-estrogen combination or
    IUDs within 72 hour of coitus.
    So, lactational amenorrhoea, oral pills and
    emergency contraceptives involve a role of
    hormone.
  • Qstn #141
    Tidal Volume and Expiratory Reserve Volume
    of an athlete is 500 mL and 1000 mL,
    respectively. What will be his Expiratory
    Capacity if the Residual Volume is 1200 mL?
    (1) 1500 mL
    (2) 1700 mL
    (3) 2200 mL
    (4) 2700 mL
    digAnsr:   1
    Ans : ( 1 )
    Sol. Tidal Volume = 500 ml
    Expiratory Reserve Volume = 1000 ml
    Expiratory Capacity = TV + ERV
    = 500 + 1000
    = 1500 ml
  • Qstn #142
    What is the fate of the male gametes
    discharged in the synergid?
    (1) One fuses with egg other(s) degenerate
    (s) in the synergid.
    (2) All fuse with the egg.
    (3) One fuses with the egg, other(s) fuse(s)
    with synergid nucleus.
    (4) One fuses with the egg and other fuses
    with central cell nuclei.
    digAnsr:   4
    Ans : ( 4 )
    Sol. In flowering plants, out of the two male
    gametes discharged in synergids, one fuses
    with the egg and other fuses with the
    secondary or definitive nucleus present in
    central cell.
    Egg (n) + 1st male gamete (n)  Zygote (2n)
    + nd
    (2n)
    (central cellnuclei)
    Secondary nucleus 2 male gamete (n)
    PEN (3n)
  • Qstn #143
    What is the site of perception of photoperiod
    necessary for induction of flowering in
    plants?
    (1) Lateral buds
    (2) Pulvinus
    (3) Shoot apex
    (4) Leaves
    digAnsr:   4
    Ans : ( 4 )
    Sol. During flowering, photoperiodic stimulus is
    perceived by leaves of plants.
  • Qstn #144
    Select the correctly written scientific name of
    Mango which was first described by Carolus Linnaeus
    (1) Mangifera indica Car. Linn.
    (2) Mangifera indica Linn.
    (3) Mangifera indica
    (4) Mangifera Indica
    digAnsr:   2
    Ans : ( 2 )
    Sol. According to rules of binomial nomenclature,
    correctly written scientific name of mango is
    Mangifera indica Linn.31
  • Qstn #145
    Following statements describe the
    characteristics of the enzyme Restriction
    Endonuclease. Identify the incorrect
    statement.
    (1) The enzyme cuts DNA molecule at
    identified position within the DNA.
    (2) The enzyme binds DNA at specific sites
    and cuts only one of the two strands.
    (3) The enzyme cuts the sugar-phosphate
    backbone at specific sites on each strand.
    (4) The enzyme recognizes a specific
    palindromic nucleotide sequence in the
    DNA.
    digAnsr:   2
    Ans : ( 2 )
    Sol. Restriction enzymes cut DNA molecules at a
    particular point by recognising a specific
    sequence. Each restriction endonuclease
    functions by inspecting the length of a DNA
    sequence. Once it finds its specific
    recognition sequence, it will bind to the DNA
    and cut each of the two strands of the double
    helix at specific points in their sugar-
    phosphate backbone.
  • Qstn #146
    From evolutionary point of view, retention of
    the female gametophyte with developing
    young embryo on the parent sporophyte for
    some time, is first observed in
    (1) Liverworts
    (2) Mosses
    (3) Pteridophytes
    (4) Gymnosperms
    digAnsr:   3
    Ans : ( 3 )
    Sol. In Pteridophyte, megaspore is retained for
    some times in female gametophyte, however
    the permanent retention is required for seed
    formation in Gymnosperms.
    That's why Pteridophytes exhibit precursor to
    seed habit only.
  • Qstn #147
    In Antirrhinum (Snapdragon), a red flower
    was crossed with a white flower and in ``F_1`` generation pink flowers were obtained. When
    pink flowers were selfed, the ``F_2``
    generationshowed white, red and pink flowers. Choose
    the incorrect statement from the following :
    (1) This experiment does not follow the
    Principle of Dominance.
    (2) Pink colour in ``F_1`` is due to incomplete
    dominance.
    (3) Ratio of ``F_2``
    is ``\frac14`` (Red) : ``\frac24``(Pink) : ``\frac14`` (White)
    (4) Law of Segregation does not apply in this
    experiment
    digAnsr:   4
    Ans : ( 4 )
    Sol. Genes for flower colour in snapdragon shows
    incomplete dominance which is an exception
    of Mendel's first principle i.e. Law of
    dominance.
    Whereas Law of segregation is universally
    applicable.
  • Qstn #148
    Conversion of glucose to glucose-6-phosphate,
    the first irreversible reaction of glycolysis, is
    catalyzed by
    (1) Aldolase
    (2) Hexokinase
    (3) Enolase
    (4) Phosphofructokinase
    digAnsr:   2
    Ans : ( 2 )
    Sol. Hexokinase catalyse the conversion of
    Glucose to Glucose-6 phosphate. It is the first
    step of activation phase of glycolysis.
  • Qstn #149
    Drug called ‘Heroin’ is synthesized by
    (1) methylation of morphine
    (2) acetylation of morphine
    (3) glycosylation of morphine
    (4) nitration of morphine
    digAnsr:   2
    Ans : ( 2 )
    Sol. Heroin, commonly called smack and is
    chemically diacetylmorphine which is
    synthesized by acetylation of morphine.
  • Qstn #150
    Select the hormone-releasing Intra-Uterine
    Devices.
    (1) Vaults, LNG-20
    (2) Multiload 375, Progestasert
    (3) Progestasert, LNG-20
    (4) Lippes Loop, Multiload 375
    digAnsr:   3
    Ans : ( 3 )
    Sol. Progestasert and LNG-20 are hormone
    releasing IUDs which make the uterus
    32
    unsuitable for implantation and the cervix
    hostile to sperms.