Question

The lower chambers of the heart are called
a. Auricles
b. Ventricles
c. Spiracles
d. Tentacles

Answer 1

Hint: The heart is the circulatory system’s main organ. In humans, the heart is composed of four chambers i.e., two upper and two lower chambers. The lower chamber of the heart is responsible for pumping blood out of the heart to different parts of the body while the upper chamber receives the incoming blood. The lower chamber of the heart is more muscular as compared to the upper chamber.

Complete answer:
> Option (A) is incorrect. Auricles are the two upper chambers of the heart i.e., left and right auricles that have thin walls and are meant for receiving the incoming blood.

> Option (B) is correct. Ventricles are the two lower chambers of the heart i.e., left and right ventricles that are more muscular than the auricles and are known for pumping blood out of the heart.

> Option (C) is incorrect. Spiracles are the openings present in the exoskeletons of the insects through which air enters into the trachea. These spiracles can open and close through the relaxation and contraction of the muscles surrounding the spiracles, respectively.

> Option (D) is incorrect. Tentacles are elongated organs that are flexible and mobile, present mostly in the invertebrates. Their role is to act as either sensory organs or to be used for grasping and feeding.

Hence, the correct answer is option (B).

Note: Two ventricles i.e. left and right are present in the lower part of the heart. The left and right auricle and the left and the right ventricle, separated by a wall of muscle called the septum. The auricle and the ventricle communicate through the opening and closing of the valves present between them. The left ventricle is the strongest and the largest chamber of the heart as compared to the other chambers.