Reproduction in Animals - Exemplar Solutions 1

CBSE Class 8 Science
NCERT Exemplar Solutions
CHAPTER 9
Reproduction in Animals

MULTIPLE CHOICE QUESTIONS

1. The following sets of reproductive terms are given below. Choose the set that has an incorrect combination.

(a) Sperm, testis, sperm duct, penis

(b) Menstruation, egg, oviduct, uterus

(d) Ovulation, egg, oviduct, uterus

Ans. (c) This is not the correct combination of reproductive organs as sperm is male gamete whereas oviduct, egg, uterus are parts of female reproductive system.

2. In humans, the development of fertilised egg takes place in the

(a) Ovary

(b) Testis

(d) Uterus

Ans. (d) Uterus is that part of the female reproductive system where further development of the embryo takes place.

3. In the list of animals given below, hen is the odd one out.

Human beings, cow, dog, hen

a) It undergoes internal fertilisation.

(b) It is oviparous.

(d) It undergoes external fertilisation.

Ans. (b) Unlike rest of the three, hen lays eggs to give birth to their young ones and hence are known are oviparous.

4. Animals exhibiting external fertilisation produce a large number of gametes. Pick the appropriate reason from the following.

(a) The animals are small in size and want to produce more offsprings.

(b) Food is available in plenty in water.

(d) Water promotes production of large number of gametes.

Ans. (c) Animals exhibiting external fertilistaion produce a large number of gametes to ensure better chances of fertilization because the eggs and sperms get exposed to the external environmental factors like water movements, wind, rainfall and predators.

5. Reproduction by budding takes place in

(a) Hydra

(b) Amoeba

(d) Bacteria

Ans. (a) Hydra

6. Which of the following statements about human reproduction is correct?

(a) Fertilisation takes place externally.

(b) Fertilisation takes place in the testes.

(d) Fertilisation takes place in the human female.

Ans. (d) Fertilization take places inside the female body and hence it is called internal fertilization.

7. In human beings, after fertilisation, the structure which gets embedded in the wall of uterus is

(a) Ovum

(b) Embryo

(d) Zygote

Ans. (b) In the phenomenon of fertilization, the male gamete called sperm fuses with female gamete called ovum. The nuclei of these gametes fuse to produce a single nucleus leading to the formation of zygote which divides repeatedly giving rise to a ball of cells leading to the development of an embryo which gets embedded in the wall of uterus for further development.

8. Aquatic animals in which fertilisation occurs in water are said to be:

(a) Viviparous without fertilisation.

(b) Oviparous with external fertilisation.

(d) Oviparous with internal fertilisation.

Ans. (b) They are known as oviparous because they give birth to their young ones by laying eggs in the watery medium and at the same time the fertilization take place outside the female body and hence is called external fertilization.

9. After fertilisation, the resulting cell which gives rise to a new individual is the

(a) Embryo

(b) Ovum

(d) Zygote

Ans. (d) Zygote

10. In human beings, the correct sequence of events during reproduction is

(a) Gamete formation, fertilisation, zygote, embryo

(b) Embryo, zygote, fertilisation, gamete formation

(d) Gamete formation, fertilisation, embryo, zygote

Ans. (a) Gamete formation, fertilisation, zygote, embryo