- how many secondary spermatocytes will be required to
form 400 spermatozoa?
(a) 40 (b) 100
(c) 200 (d) 400
- The ‘cells of rauber’ are
(a) secretory cells of endometrium in uterus
(b) inner cell mass of blastocoel
(c) outer cells of trophoblast in contact with uterine
wall
(d) cells of trophoblast, in contact with inner cell mass
of blastocyst.
- Why cannot a woman get pregnant again during
pregnancy?
(a) a woman ovulates during pregnancy, but the
oviducts are plugged with protective mucus to
prevent sperm from entering.
(b) high levels of hcG in woman’s body kill sperm.
(c) a woman cannot have intercourse during pregnancy.
(d) high levels of estrogen and progesterone, secreted
by the corpus luteum or placenta during pregnancy,
inhibit the secretion of gonadotropins and prevent
ovulation.
- The correct floral formula of soyabean is
(a)
(b)
(c)
(d)
- match the following and choose the correct combination
from the options given below.
Column-I Column-II
(Population (Examples)
interaction)
a. mutualism 1. Ticks on dogs
B. commensalism 2. Semibalanus and Chthamalus
c. Parasitism 3. Sparrow and any seed
D. competition 4. Epiphyte on a mango branch
E. Predation 5. Fig and wasp
(a) a – 1, B – 5, c – 4, D – 3, E – 2
(b) a – 2, B – 1, c – 5, D – 4, E – 3
(c) a – 3, B – 2, c – 1, D – 5, E – 4
(d) a – 5, B – 4, c – 1, D – 2, E – 3
- The Bt toxin is not toxic to human beings because
(a) the pro Bt toxin activation requires temperature
above human body temperature
(b) the Bt toxin recognizes only insect-specific targets
(c) the Bt toxin formation from pro Bt toxin requires ph
lower than that present in human stomach
(d) conversion of pro Bt toxin to Bt toxin takes place
only in highly alkaline conditions.
- If S = species richness, a = area, Z = slope of the line
(regression coefficient), c= Y-intercept, then the relation
between species richness and area is described on a
logarithmic scale by the equation
(a) log S = log c – Z log a
(b) log S = Z log a
(c) log S = log c + Z log a
(d) log c = log S + Z log a.
- Given pie diagram represents the proportionate number
of species of major taxa of plants. Select the incorrect
statements regarding a and B.
(i) a represents the achlorophyllous, heterotrophic,
eukaryotic organisms with chitinous cell walls.
(ii) B represents the members of Kingdom monera e.g.,
bacteria and cyanobacteria.
(iii) B represents those seed plants in which seeds are
enclosed inside fruits.
(iv) a and B represent gymnosperms and angiosperms
respectively.
(a) (i) and (iv) (b) (ii) and (iv)
(c) (i) and (iii) (d) (ii), (iii) and (iv)
- The graph below represents changes in different
ecological parameters due to effluent mixing in a stream.
The three lines a, B and c represent:
(a) a: oxygen concentration
B: biological O 2 demand
c: pollution resistant species
