Write two points of difference between asexual and sexual types of reproduction. Describe why variations are observed in the offspring formed by sexual reproduction.

5

(a)

Distinguish between a gamete and zygote. Explain their roles in sexual reproduction.

5

(a)

How does fertilisation take place? Fertilisation occurs once in a month. Comment.

5

(a)

What is the placenta? Mention its role during pregnancy?

5

(a)

Reproduction is essentially a phenomenon that is not survival of an individual but for the stability of a species. Justify.

5

(a)

(a) Name the human male reproductive organ that produces sperms and also secretes a hormone. Write the functions of the secreted hormone.
(b) Name the parts of the human female reproductive system where
(i) fertilisation takes place,
(ii) implantation of the fertilised egg occurs.
Explain how the embryo gets nourishment inside the mother's body.

5

(a)

List four points of significance of reproductive health in a society. Name any two areas related to reproductive health which have improved over the past 50years in our country.

5

(a)

(a)Give one example each of a unisexual and a bisexual flower
(b)Mention the changes a flower undergoes after fertilisation.
(c)How does the amount of DNA remain constant though each new generation is a combination of DNA copies of two individuals?

5

(a)

(a)Identify A, B and C in the given diagram and write their functions.
(b)Mention the role of gamete and zygote in sexually reproducing organisms.

5

(a)

Describe in brief the role of (i)testis (ii)seminal vesicle, (iii)vas deferens, (iv)ureter and (v) prostate gland in human male reproductive system.

5

(a)

Write the two causes of human population explosion. Explain with the help of suitable examples how this explosion can be checked.

5

(a)

(a) Name the parts labelled as A,B,C and D in the diagram given below:

(b) What is pollination? State its significance.
(c) How does fertilisation occur in flowers? Name the parts of the floower that develop into 
(i) seed, and (ii) fruit after fertilisation.

5

(a)