Answer: 3. 7-10% of CO2 is dissolved directly into the plasma
Step-by-step explanation:
Carbon dioxide molecules are transferred by one of three methods into the blood from body tissues to the lungs including binding to haemoglobin, movement as a bicarbonate ion and absorption directly into the blood. Various carbohydrate properties in the blood influence its movement that are as following:
- Carbon dioxide is more soluble than oxygen in the blood. The plasma dissolves about 5 to 7 per cent of all carbon dioxide.
- Carbon dioxide may bind to plasma proteins, or may penetrate red blood cells and bind to haemoglobin and form carbaminohemoglobin which cover 20% of CO2.
Hence, the correct option is 3.