Question

Assertion: Blood takes up oxygen from the alveolar air and release carbon-dioxide during exchange.

Reason: The concentration of oxygen is more in alveolar air.
A) Both A and R are true and R is the correct explanation of A
B) Both A and R are true but R is not the correct explanation of A
C) A is true but R is false
D) A is false but R is true.

Answer 1

Answer:

b will be the correct answer

Answer 2

1. The correct answer to the above question is- B) Both A and R are true but R is not the correct explanation of A.

• During breathing, we inhale oxygen-rich air and exhale carbon dioxide rich air. The air goes into the alveoli of lungs.
• At alveoli, various factors favour the exchange of gases. These are- partial pressure gradient, the thickness of membranes involved in diffusion and solubility of gases.
• When all factors are favourable, the oxygen is diffused into the blood vessels while carbon-dioxide is dissociated from haemoglobin and released into the alveoli.