Given below is a diagrammatic sketch of the vertical section of human skin.

(a) Label the parts numbered 1 to 9

(b) State one main function of each of the following parts:

1. Part 2.
2. Part 3.
3. Part 4.
4. Part 9.

(c) Name any one of the above parts which has at least three functions.

(d) Part 4 may add to one's good appearances or the "figure". State one example of this function which may be common to both men and women.

The figures A and B given below represent the ways of heat regulation in our body with the help of blood vessels. Study the figures and answer the following questions.

(a) Name the process/condition shown in figures A and B.

(b) During what climatic conditions, do these processes occur in our body?

(c) What colour change do we see in the facial appearance of a person during these situations?

(d) Do these situations occur due to emotional causes? If yes, name them.

Why are body hairs present in mammals?

This structure in birds is a counterpart of mammalian hair.

1. What is this? ……………
2. What is the one common primary function served by these structures both in birds and mammals?