Question

How does the transport of O₂ and CO₂ by blood happen?

• A. With the help of platelets and corpuscles
• B. With the help of WBCs and blood serum
• C. With the help of RBCs and WBCs
• D. With the help of RBCs and blood plasma

Answer 1

The correct option is D

With the help of RBCs and blood plasma

The correct option is D:

Explanation for the correct option:

1. In blood, oxygen and carbon dioxide are carried by RBC and blood plasma.
2. 97% of oxygen is transported by RBC and the rest of the 3% is by the plasma.
3. In the RBC, hemoglobin (respiratory pigment) is found that binds the oxygen and form oxyhemoglobin.
4. 70% of the carbon dioxide is carried by RBC. In RBC, carbonic anhydrase enzyme is found. Carbon Dioxide forms carbonic acid.
5. 20 - 25% of carbon dioxide is carried by RBC in the form of carbamino-hemoglobin.
6. The rest of the 7% of the carbon dioxide is dissolved in blood plasma.

Explanation for the incorrect option

Option A: Platelets have no role in carrying oxygen and carbon dioxide but these help in blood clotting.

Option B: WBC and blood serum do not carry gases. WBC is the protective cells that help to kill pathogens. Blood serum help in the transportation of various substances.

Option C: RBC carries oxygen and carbon dioxide but WBC doesn't. WBC are the cells that are related to our immune system.

Final Answer: Oxygen and carbon dioxide are transported in the blood by RBC and blood plasma.