Class 8 Science Chapter 6 Practice Question Answers - Reproduction in Animals

Q1: What is reproduction?
Ans: Reproduction is the biological process by which new individual organisms are produced from their parents.

Q2: What is sexual reproduction?
Ans: Reproduction which involves the fusion of male and female gametes is known as sexual reproduction.

Q3: What is fertilisation?
Ans: The fusion of ova and sperm is called fertilisation.

Q4: What is a fertilised egg called?
Ans: Zygote

Q5: What is asexual reproduction?
Ans: The mode of reproduction in which only a single parent is involved.

Q6: Which mode of reproduction does take place in human beings?
Ans: Sexual reproduction

Q7: How many partners involve in sexual reproduction?
Ans: Two (Parents)

Q8: Name two animals in which asexual reproduction takes place.
Ans: Hydra and yeast

Q9: __________ is the process that ensures continuity of life on earth.
Ans: Reproduction

Q10: __________ are the cells involved in sexual reproduction.
Ans: Gametes

Q11: The animals which lay eggs are called __________.
Ans: oviparous

Q12: The animals which give birth to young ones are called __________.
Ans: viviparous

Q13: __________ is the process of fusion of gametes.
Ans: Fertilisation

Q14: The process of reproduction involving fusion of male and female gametes is called __________ reproduction.
Ans: sexual

Q15: The number of modes by which animals reproduce are
(a) two
(b) three
(c) four
(d) none of these
Ans: (c)
Explanation: Animals can reproduce through four main modes: asexual reproduction, sexual reproduction, hermaphroditism (a combination of both male and female reproductive structures in the same organism), and parthenogenesis (reproduction from unfertilized eggs). These modes provide animals with diverse strategies for reproduction.

Q16: Binary fission is observed in
(a) Hydra
(b) yeast
(c) Amoeba
(d) human being
Ans: (c)
Explanation: Binary fission is a type of asexual reproduction observed in single-celled organisms like Amoeba. In binary fission, the cell divides into two nearly equal daughter cells, each of which grows to the size of the parent cell and then divides again.

Q17: Asexual reproduction is observed in
(a) cow
(b) buffalo
(c) sponge
(d) hen
Ans: (c)
Explanation: Asexual reproduction is observed in various organisms, including sponges. Sponges can reproduce asexually through processes like budding, where a small outgrowth (bud) forms on the parent organism and eventually detaches to become a new individual.

Q18: In Hydra, the mode of reproduction is
(a) asexual
(b) sexual
(c) both (a) and (b)
(d) none of these
Ans: (c)
Explanation: Hydra can reproduce through both asexual and sexual modes. Asexually, Hydra reproduces by budding, where a small bud grows on the body of the parent and eventually detaches to become an independent individual. Sexually, Hydra can produce eggs and sperm, allowing for sexual reproduction as well.

Q19: The animals that produce new young ones are called
(a) viviparous
(b) oviparous
(c) both
(d) none of these
Ans: (c)
Explanation: Both viviparous and oviparous animals produce new young ones, but they do so using different reproductive methods. Viviparous animals give birth to live offspring after the embryos have developed inside the mother's body. Oviparous animals lay eggs, and the embryos develop and hatch outside the mother's body.

Value-Based Questions

Q20: Ram with his family went to a picnic spot near a pond. He saw some jelly-like mass floating on the sides of the pond. He asked about this to his father. His father explained him that these are frog’s egg and are millions in number. Ram wondered if all of them get hatched, what will happen to other aquatic animals?

1. What type of fertilisation is shown by frog?
2. Why do frog lay eggs in large amount?
3. Is Ram’s concern about hatching of too many eggs at a time will affect the aquatic animals correct? Why?
4. What Value of Ram is shown here?

Ans:

1. Frog shows external fertilisation.
2. Mortality rate is very high for tadpoles as their predators are more. Many of the eggs do not develop due to being not get fertilised. So for continuation of their species, they lay egg in large amount.
3. No, his concern is not correct because most of the eggs either never develops or are preyed by other animals. So survival chance of a frog from its egg to an adult frog is very low.
4. Ram is inquisitive, future thinker and eco-concerned.