- Read the following statements and select the correct option.
Statement A : Reproductive isolation gives rise to
parapatric speciation.
Statement B : A physical barrier exists in parapatric
speciation.
(a) Both statements A and B are correct and B is the
correct explanation of statement A.
(b) Both statements A and B are correct but B is not
the correct explanation of statement A.
(c) Statement A is correct but statement B is incorrect.
(d) Both statements A and B are incorrect.
- Consider the following statements and choose the correct
option.
I. Increase in melanised moths after industrialisation
in England is an example of artificial selection.
II. When more individuals in a population acquire a
mean character value, it is called disruption.
III. Constant gene frequencies due to absence of gene
flow leads to Hardy-Weinberg equilibrium.
I V. Genetic drift changes the frequencies of alleles in a
population.
(a) I and III (b) II and IV
(c) I and II (d) III and IV - The tendency of population to remain in genetic equilibrium
may be disturbed by
(a) lack of mutations (b) random mating
(c) lack of random mating (d) lack of migration. - A species of a bird in coast of South America follows Hardy-
Weinberg population principle for beak colour. Dominant
phenotype is represented by a black beak, while the
recessive phenotype is represented by grey beak. If half of
the population carries recessive allele, what percentage of
the birds have black beaks?
(a) 25% (b) 50% (c) 75% (d) 100% - Match column I with column II and choose the right option.
Column I Column II
I. Thomas Malthus A. Branching descent
II. Hugo de Vries B. Studies on populations
III. Charles Darwin C. Use and disuse theory
I V. Lamarck D. Saltation
(a) I-D, II-A, III-C, IV-B (b) I-B, II-D, III-A, IV-C
(c) I-B, II-D, III-C, IV-A (d) I-C, II-B,III-A, IV-D - Select the incorrect statement regarding Peking man.
(a) They had a cranial capacity ranging between 850-
1100 cc.
(b) They made excellent ornaments of elephant tusks.
(c) They were omnivorous and cannibal.
(d) They used to live in small groups or tribes.
15. The factors contributing towards post zygotic isolation in a
population are
(i) incompatibility (ii) seasonal isolation
(iii) hybrid inviability (iv) hybrid sterility
(v) mechanical isolation
(a) (i), (ii) and (iv) only (b) (ii), (iii) and (v) only
(c) (ii) and (v) only (d) (iii) and (iv) only
16. Darwin was influenced by Malthus’ theory of human
population which states that
(a) population grows arithmetically when unchecked.
(b) a balance between the population and environment
is maintained due to competition for resources.
(c) imbalance after a certain level in a population leads
to crash caused by various factors such as hunger,
floods, epidemics, etc.
(d) none of these.
17. Identify the correct pre-historic man, from the given
characteristics.
(i) About 1.8 m tall with well built body.
(ii) Broad and arched forehead with well developed chin.
(iii) They could walk and run faster.
(iv) They made excellent tools and cave paintings.
(a) Cro-Magnon man (b) Neanderthal man
(c) Heidelberg man (d) Java ape man
18. A small population of rats including approximately equal
number of brown and white rats existed in a village on an
island. After flooding, only a few rats managed to escape
and survive while the entire population of rats in village was
carried away. The population that grew thereafter, comprised
of brown rats only, eliminating white rats completely. This
phenomenon can be described as
(a) founder effect (b) saltation
(c) bottleneck effect (d) disruptive selection.
19. The apes are more closely related to humans than the new
world monkeys and tarsiers. It can be best established by
evidences obtained from
(a) banding patterns of chromosome number 3 and 6.
(b) 100% homology in haemoglobin of humans and apes.
(c) both man and ape share only blood group A.
(d) both (a) and (b).
20. Darwin’s theory of Natural selection did not believe in role
of which of the following in organic evolution?
(a) Parasites and predators as natural enemies
(b) Struggle for existence
(c) Survival of the fittest
(d) Discontinuous variations
ANSWER KEY
- (b) 2. (a) 3. (d) 4. (d) 5. (a)
- (b) 7. (c) 8. (c) 9. (c) 10. (d)
- (b) 12. (c) 13. (b) 14. (b) 15. (a)
- (c) 17. (a) 18. (c) 19. (a) 20. (d)