Reproduction in Organisms Practice Questions - DPP for NEET

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DPP /CB23
1. (c)
2. (b) Cloning is a technique by which genetically same individuals
can be produced without including any sexual reproduction
eg. Dolly sheep.
3. (d) 4. (d)
5. (b) The parents that have survived to reproduce asexually are
able to survive in the current stable environment. Therefore,
the offspring should be preadapted for this stable
environment.
6. (a) Species that exhibit parthenogenesis develop from
unfertilized eggs produced by the mother. Therefore, the
genetic make-up should be 100 percent the same as the
mother.
7. (a) Since external fertilization can only take place in an aquatic
habitat, there are no terrestrial animals that use it.
8. (a) Many animals reproduce both by asexual and sexual means.
9. (b) All these animals can reproduce sexually. However, only the
chicken lays an external egg.
10. (b) All of these statements concerning asexual reproduction are
correct, except that asexual reproduction is best in favorable,
stable environments, ones that don’t change rapidly. The
reason for this is that asexual reproduction, in contrast to its
sexual counterpart, results in the formation of identical
offspring. Although asexual organisms can often produce many
more offspring in a single reproductive event than sexual
organisms, these asexually produced young do not usually
have the genetic variation caused by meiosis and crossing-
over to be able to survive a rapidly changing environment or
times of environmental stress.
11. (a) Buds in ‘eyes’ form new plants.
12. (b) Bud giving rise to new plant is present towards base.
13. (b) New plants in cane-sugar are formed from nodes which are
absent.
14. (b) Water absorption & gaseous exchange stop due to presence
of wax
15. (c) Parthenocarpy is the development of a fruit without the
formation of seeds as a result of lack of pollination, lack of
fertilization and lack of development. This condition can be
artificially induced by application of hormones.
16. (a) 17. (a) 18. (a) 19. (d)
20. (c) Most of banana varieties are triploid and triploidy is associated
with seedlessness.
21. (d) 22. (b) 23. (b) 24. (a) 25. (d)
26. (a) Homothallic and monoecious are terms used to denote bisexual
condition. The example indudes fungi and plants. Heterothallic
and dioecious are terms used to denote unisexual condition.
27. (b) Morphallaxis is a mechanism of regeneration involving reor-
ganization of body cells. In epimorphosis, new cells prolif-
erate from the surface of the wound to form the missing
structure. In accretionary growth some specialized cells re-
tain the ability to divide and produce new cells to replace the
worn-out.
28. (a) Cells become variable in shape, size & getting their special-
ization for the formation of particular tissue or organ in fu-
ture foetus. They place themselves at some specific regions
in embryo for further organogeny.
29. (d) Earthworm, sponges, tapeworms are bisexual animals and
hermaphrodites as they prossess both male and female
reproductive organs.
30. (c)
31. (c) Sowing is related with sexual reproduction.
32. (c) Vegetative propagation in mint occurs through sucker.
Vegetative reproduction is a type of asexual reproduction for
plants, and is also called vegetative propagation, vegetative
multiplication, or vegetative cloning. It is a process by which
new plant “individuals” arise or are obtained without
production of seeds or spores. It is a natural process in many
plant species (as well as non-plant organisms such as bacteria
and fungi) and used or encouraged by horticulturists to obtain
quantities of economically valuable plants. A related technique
used in cultivation is tissue culture, which involves vegetative
reproduction under sterile conditions.
33. (d) Vegetative reproduction and apomixis, both are asexual
methods of reproduction, which gives the progeny genetically
similar to parent.
34. (c) 35. (c) 36. (b) 37. (d) 38. (d)
39. (c) 40. (d)
41. (b) In oomycetes female gamete is large and non motile while
male gamete is small & motile.
42. (c) Male  sex organ is called antheridium or globule while female
sex organ is called oogonium. They develop on the same
branchlet in the same plant in chara.
43. (c)
44. (c) In most aquatic organisms, such as a majority of algae and
fishes as well as amphibians, syngamy occurs in the external
medium (water), i.e., outside the body of the organism. This
type of gametic fusion is called external fertilisation.
45. (d)