( a) Explain giving reasons why the tourists visiting Rohtang Pass or Mansarovar are advised to resume normal ‘active life’ only after a few days of reaching there.
(b) It is impossible to find small animals in the polar regions. Give reasons.

Explanation

(a) Initially the person suffers from altitude sickness/nausea, fatigue and heart palpitation because of low oxygen availability and low atmospheric pressure. Gradually the body increases RBC production, decreasing binding capacity of HB and increases the breathing rate to get acclimatised.
(b) Small birds have larger surface area relative to their volume, 30 they lose heat much faster and have to spend more energy to generate body heat through matabolism.