Give reasons/Explain:

(a) Skin can be considered as an accessory excretory organ.

(b) A normal healthy young person can start perspiring even when the outside atmosphere is intensely cold.

(c) Hairs can be used in forensic investigation.

(a) Skin assists in the process of excretion of water, salts and to a very limited extent, urea through sweating. Since sweating occurs mainly for temperature regulation hence skin can be considered as an accessory excretory organ.

(b) A normal healthy young person can start perspiring even in cold atmosphere due to psychic influences such as fright or nervousness. This is referred to as "cold sweat".

(c) Hairs from different part of body show subtle differences. Hair follicles, found at the root of the hair, have the highest concentration of DNA, making them particularly valuable for DNA analysis. Therefore, hairs can be used in forensic investigation.