Which of the following statements with reference to 'blood' is/are correct? 1. Blood is composed of plasma and different types of…

Question

Which of the following statements with reference to 'blood' is/are correct?

1. Blood is composed of plasma and different types of cells.

2. The presence of haemoglobin makes blood appear red.

Select the correct answer from the code given below:

1. A. Only 2
2. B. Neither 1 nor 2
3. C. Both 1 and 2 (Correct answer)
4. D. Only 1

Correct Answer

Option C — Both 1 and 2

Detailed Solution & Explanation

The correct answer is Both 1 and 2.

Key Points

• Statement 1 is correct. Blood is a fluid connective tissue made of plasma (about 55%) and formed elements (about 45%) — erythrocytes (RBC), leucocytes (WBC) and thrombocytes (platelets).
• Statement 2 is correct. The red colour of blood comes from haemoglobin, the iron-containing pigment in red blood cells.
• Both hold, giving option (c).

Additional Information

• Plasma is about 90-92% water, with proteins (albumin, globulin, fibrinogen), salts, glucose, hormones and wastes. Serum is plasma minus the clotting factors.
• RBCs in mammals are enucleated and biconcave, live about 120 days, and are formed in the bone marrow and destroyed in the spleen — the "graveyard of RBCs".
• Haemoglobin binds oxygen as oxyhaemoglobin. Its far greater affinity for carbon monoxide — roughly 200-250 times — is what makes CO lethal.
• WBCs are nucleated and defend the body; the five types are neutrophils, eosinophils, basophils (granulocytes) and lymphocytes, monocytes (agranulocytes). Neutrophils are the most abundant.
• Blood groups follow the ABO system discovered by Karl Landsteiner: O negative is the universal donor and AB positive the universal recipient.