Question

Study the given diagram of the heart, with blood vessels marked ‘1’ and ‘2’.

From the following statements, establish the relationship between heart and/or the two blood vessels:

1. Blood vessel 1 - It carries carbon dioxide rich blood to the lungs.
2. Blood vessel 2 - It carries oxygen rich blood from the lungs.
3. Blood vessel 2 - Left atrium relaxes as it receives blood from this blood vessel.
4. Blood vessel 1 - Right atrium has thick wall as it has to pump blood to this vessel.

The option with correct statements is:

Options

• (i) and (ii)

• (ii) and (iii)

• (ii), (iii) and (iv)

• (i), (ii) and (iii)

Answer 1

(i), (ii) and (iii)

Explanation:

Blood vessel ‘1’ is the pulmonary artery, carrying CO₂-rich blood from the heart to the lungs. Statement (i) is correct. Blood vessel ‘2’ is the pulmonary vein, bringing O₂-rich blood to the left atrium, which relaxes while receiving it. Statements (ii) and (iii) are correct. Statement (iv) is incorrect because the right atrium has thin walls, not thick.