question_answer

Observe the following figures.
(a)	(b)
(c)	(d)
(i) Identify the stages (a) to (d) in figures during development of human baby.
(ii) Arrange the stages in correct sequence of development.
(iii) Explain the development that takes place in any one stage.

Answer:

(i) The given figures showing stages during development of embryo are identified as :

(a) Embedding of the embryo in the uterus (implantation)

(b) Fertilisation (fusion of egg and sperm)

(c) Zygote formation and development of an embryo from the zygote.

(d) Zygote (showing fusion of gametes) single celled.

(ii) The above stages in sequence are:

(a) Implantation of embryo in uterus, (d)

(b) Fertilisation (a)

(c) Development of embryo (c)

(d) Zygote formation (b)

(iii) The embryo after being implanted in uterus, continues to develop and divide and differentiate into body parts. This stage of embryo where body parts are distinct and identified is called foetus.

After the complete development of foetus, the mother gives birth to baby.