BIOLOGY TIMES — January 2018

(ff) #1
EVA AITS (NEET [BOTANY] -9)


  1. (a) If a Rhwoman is married with a Rh+ man , she
    becomes sterilised easily by carrying a Rh+ child
    within her body.Though during development,
    some cells from the embryo might get mixed
    into her blood stream. Therefore, the first child
    of the parents with such genetic history is almost
    normal always and will survive.

  2. (b)

  3. (d) Microbodies are single membrane covered
    small cell organelles which take part in oxidation
    reactions other than those of respiration. They
    are of different kinds that include Peroxisomes,
    Glyoxysomes and Melanosomes.

  4. (b) Predation is not a factor in which productivity
    of an ecosystem depends. Predation is an
    interaction where one animal which acts as a
    predator will kill and consume another animal.
    (prey)

  5. (d) Meselson and Stahl in 1958 supported the
    hypothesis that DNA replication was semi-
    conservative. They proved this by using cultured
    in E.coli in a cultural medium containing^15 N
    isotopes of heavy nitrogen. After the DNA
    replication of E.coli for some generations in^15 N
    medium, it was found that both strands of DNA
    had^15 N as constituent of purines and pyrimidines.
    Therefore, such DNA formed was found to be
    hybrid as one strand which was made up of^15 N
    (old) and the other was made up of^14 N (new).

  6. (b) Taq Polymerase has thermostable property
    as the bacteria from which it is extracted also
    contains such property.

  7. (d) Palisade tissue are elongated columnar cells
    without intercellular spaces. These cells have
    large number of chloroplasts. They take part in
    photosynthesis.

  8. (d) During cellulose fermentation by anaerobic
    bacteria in rumen and reticulum, Cellulose is
    mainly changed into Volatile fatty acid.

  9. (c) Since Calvin cycle is a dark reaction and
    oxygen is released during the light reaction.
    10. (a) As the Earth is covered by 75% water hence
    aquatic ecosystem is found to occur in the largest
    surface area.
    11. (d) 12. (b)
    13. (b) Necrosis is the death of cells and tissues that
    causes brown spots.
    14. (c) Complete darkness shows etiolation.
    15. (a) Gemma cups are found in Marchantia, a
    bryophyte, it is cup-shaped structure specially
    meant for vegetative propogation.
    16. (d) Exine is made up of sporopollenin which is
    derived from carotenoids.
    17. (b) In Klienefelter’s syndrome (or 47, XXY),
    there are some special symptoms which include
    weaker muscles, greater height, poor coordination,
    less body hair, smaller genitals, breast growth,
    and less interest in sex. Such symptoms are
    noticed only at puberty. The special feature of
    this condition is the increase in size of male breast
    tissue (like female breast development) and this is
    termed as Gynecomastia which is a common
    endocrine system disorder.
    18. (d) Perennials survive for more than two years
    and produce flowers and fruits during specific
    seasons.
    19. (a) Cristae are folded structures of the inner
    membrane of mitochondria that create more space
    to allow for a faster energy production.
    20. (b) Statement D is wrong, Hydrosere is a biotic
    succession that occurs in an aquatic habitat.
    21. (b) A synthesised RNA transcript undergoes many
    levels of processing called post transcriptional
    modification in Eukaryotes. Taking an example
    of mRNA, modification is important to convert
    pre-mRNA into a mature mRNA which is ready
    for protein translation. Splicing is one such
    modification.

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