Question

The blood leaving the lungs has its haemoglobin oxygenated and unloads its oxygen to the tissues, because
(2) (3) (4)

• A. The tissues can absorb $O_2$ from oxyhaemoglobin
• B. $O_2$ concentration in tissues is lower and ${CO}_2$ concentration higher than that of lungs
• C. $O_2$ concentration in tissues is higher and ${CO}_2$ concentration lower than that of lungs
• D. Oxyhaemoglobin undergoes reduction

Answer 1

The correct option is B $O_2$ concentration in tissues is lower and ${CO}_2$ concentration higher than that of lungs

As blood passes through the lungs, haemoglobin along with oxygen is carried to tissues. There is an increased oxygen pressure in the capillaries of lungs and it is released where the pressure is low i.e. tissues.The carbon dioxide is then released once the red blood cells reach the lungs. So option 'O2 concentration in tissues is lower and CO2 concentration higher than that of lungs' is correct.