Heart

Q. Semilunar valves guard the opening of :​

1. Pulmonary artery which carries blood from ventricle to lungs for oxygenation.
2. Both (A) & (B) are correct.
3. Aorta which carries blood from left ventricle to rest of the body for distribution.
4. Atrium into ventricles of respective sides to prevent blood flow in reverse direction.

Q. Select the incorrect statement about pumping of blood by the human heart:

1. Carbon dioxide rich blood is sent to the heart by all the organs.
2. Carbon dioxide rich blood is sent to the heart by the lungs.
3. Deoxygenated blood is the same as carbon dioxide rich blood.
4. Oxygenated and deoxygenated blood are separated.

Q. _______ are present to prevent backflow of blood in the heart.

Q. In frogs, blood passes twice through the heart. Hence, they are said to have a _____ circulation.

Q. Deoxygenated blood contains less carbon dioxide.

1. True
2. False

Q. Select the correct statements about the heart.

1. Blood flows at tremendous pressure through the heart, so valves are absent.
2. Deoxygenated blood flows on the right side and oxygenated blood flows on the left side.
3. The atrium and the ventricle on the right side contract simultaneously, and the atrium and the ventricle on the left side contract simultaneously.
4. The two atria contract simultaneously, and the two ventricles contract simultaneously.

Q.
In the given diagram, which of the following contract together? Select the correct options.

1. A and B
2. B and D
3. C and D
4. A and C

Q.

Match the following:
$\begin{array}{cc}\text{(i) Amphibians and most reptiles}& \text{A. 2-chambered heart}\\ \text{(ii) Birds and mammals}& \text{B. 3-chambered heart}\\ \text{(iii) Fish}& \text{C.4-chambered heart}\end{array}$

1. i - A, ii - B, iii - C

2. i - A, ii - C, iii - B

3. i - B, ii - C, iii - A

4. i - C, ii - A, iii - B

Q. In the human heart, oxygenated and deoxygenated blood are separated.

1. True
2. False

Q. Which of these statements are correct?
(i) All vertebrates have four-chambered hearts.
(ii) Deoxygenated and oxygenated blood are separated in animals with high energy needs.
(iii) Fish have a double circulation.

1. (i)
2. (ii)
3. (i), (ii) and (iii)
4. (iii)