- an inter-breeding population of finches became
separated geographically, forming two isolated groups.
Each group then became subject to different selective
pressures. One group was then introduced into the
habitat of the other.
Which one of the following would determine whether
they now formed two distinct species?
(a) They had been separated for more than three million
years.
(b) They failed to produce fertile F 1 hybrids.
(c) They showed marked differences in the shape of
their beaks.
(d) Their plumage had become markedly different.
- The extinct human who lived 1,00,000 to 40,000 years
ago, in Europe and asia, with short stature, heavy eye
brows, retreating fore heads, large jaws with heavy teeth,
stocky bodies, a lumbering gait and stooped posture
was
(a) Homo habilis (b) Neanderthal man
(c) cro-magnon man (d) Ramapithecus.
- In habitual alcohol drinkers, liver gets damaged because
of
(a) accumulation of excess glycogen
(b) accumulation of excess fat
(c) excess detoxification
(d) excess deamination.
- The process of transformation is not affected by which
of the following enzymes?
a. DNase B. rNase
c. Peptidase D. Lipase
(a) a, B (b) a, B, c, D
(c) B, c, D (d) a, B, c
- read the following statements and choose the correct
option.
a. Increase in melanised moths after industrialization
in Great Britain is a proof for natural selection.
B. When more individuals of a population acquire a
mean character value, it is called disruption.
c. changes in allelic frequency in a population will
lead to hardy-Weinberg equilibrium.
D. Genetic drift changes the existing gene or allelic
frequency in future generations.
(a) B alone is correct.
(b) D alone is correct.
(c) a and D alone are correct.
(d) a and c alone are correct.
- refer the given statements.
(i) Incomplete or mosaic inheritance is an example of
pre-mendelian concept of blending inheritance.
(ii) Test cross is a special type of back cross.
(iii) chromosomal aberrations are commonly observed
in cancer cells.
(iv) Thalassaemia is a mendelian disorder.
Which of the above statements are correct?
(a) (i) and (ii) only (b) (ii), (iii) and (iv)
(c) (ii) and (iv) only (d) (i) and (iv) only
- Study the given pedigree chart showing the inheritance
of an X-linked trait controlled by gene ‘r’.
A B
C D
P
F 1
F 2
What will be the genotypes of individuals a, B, c and D
respectively?
(a) XX, XrY, XrX, XY
(b) XrXr, XY, XX, XY
(c) XrX, XrYr, XrXr, XrY
(d) XX, XrYr, XX, XY
- read the following statements and choose the incorrect
option.
(a) Phosphate group is linked to 5’-Oh of a nucleoside
through phosphoester linkage.
(b) Two nucleosides are linked through 3’ – 5’
N-glycosidic linkage.
(c) Negatively charged DNa is wrapped around
positively charged histone hectamer to form
nucleosome.
(d) The chromatin that is more densely packed and
stains dark is called heterochromatin.
- The following table shows the base ratios for DNa
collected from four different animals species a, B, c, D.
Which species is likely to contain DNa with an adenine
concentration of 21.1%?
Species Cytosine Guanine Thymine
(a) a 31.6 32.4 18.0
(b) B 29.6 29.2 20.1
(c) c 24.8 28.9 25.4
(d) D 32.1 31.9 17.6