Biology Times March 19
14.Sol: Energy for muscle contraction is derived
from hydrolysis of ATP by ATPase of myosin.
15.Sol: Gastronemius muscle is located in the
shank region.
16.Sol:A.Cervical nerves – 8 pairs
B. Thoracic nerves – 12 pairs
C. Lumbar nerves – 5 pairs
D. Coccygeal nerves – 1 pair
17.Sol:Organ of Ruffini are mechanoreceptors
which are responsible to sense the stretch in the
skin, pressure on theskin and also perception of
heat.
18.Sol: Choroid is a black pigmented layer under
the sclera that prevents the internal reflection of
light rays in eye. It is filled with blood capillaries.
19.Sol: Cholesterol serves a variety of functions
in human body. This includes:
The manufacture of steroids, or cortisone-like
hormones, including vitamin D and the sex
hormones testosterone, estrogen and cortisone.
Thus, both Assertion and Reason are true and but
Reason is not the correct explanation of Assertion.
20.Sol: Except aldosterone all the given options have
some role in the metabolism of sugar in the body.
22.Sol: Retina, epidermis and brain are derived
from ectoderm.
24.Sol: Cowper’s glands were named after William
Cowper an English surgeon. These are found in
male mammals.
25.Sol: IUI stands for intra uterine insemination.
26.Sol: Asthenospermia refers to reduced motility of
sperms.
29.Sol: In primordial atmosphere, there was no
oxygen or less oxygen. Hence the organisms
were anaerobes.
32.Sol: Macrophages are a type of white blood
cells that engulfs and digests the debris, foreign
substances, cancer cells, and other unwanted
microscopic particles and dead cells.
Macrophages are born from white blood cells
called monocytes.
33.Sol: Base of the pyramid represented by
prereproductive followed by reproductive and
apex by post reproductive individuals
34.Sol: Predation is an interaction where one
organism kills another organism (prey).
36.Sol: Biomass, is the mass of living biological
organisms in a given area or ecosystem at a
given time. Forest are found in the region where
there is abundant warmth and rainfall. Forest are
inpenetrable with maximum diversity. Hence
biomass is highest in forest ecosystem
37.Sol: Decomposers feed on dead and decaying
matter, converting it into inorganic chemicals that
can be recycled as mineral nutrients for plants to
use again. So if decomposers are removed , flow
of nutrients will stop.
38.Sol: Pyramid of energy is always upright
indicates that herbivore is consumed by a
carnivore. Here herbivore is primary consumer and
carnivore is the secondary consumer. As energy
passes into higher trophic levels along with food,
its amount decreases because of its dissipation as
heat and use in overcoming entropy as well as for
performing various body activities.
42.Sol: As prescribed by Central Pollution Control
Board, BOD limit for discharge of industrial
and municipal waste water is ˂10 ppm.
43.Sol: Lobaria pulmunaria is lichen which is a
bioindicator of air pollution.
44.Sol: Organic waste from kitchen and Pollution
from animal excreta can be used in gobar gas
plants which will enrich manure and also
provide gas for domestic use.
45.Sol: More release of SO 2 and NO 2 produced by
burning fossil fuels leads to the formation of Acid
rain.
