Question

Heart pumps only impure blood in case of
(a)Sharks
(b)Whale
(c)Lizard
(d)Frog

Answer 1

Hint Impure blood is referred to as deoxygenated blood. In a human heart, deoxygenated blood from the body is pumped into the right atrium and then into the right ventricle which pumps it to the lungs where it becomes oxygenated again.

Complete Answer:
Only impure blood flows through the heart in case of a single circulation. In a single circulation, deoxygenated blood from the blood flows to the heart which then pumps it to the gills. This is where the blood becomes oxygenated and flows to the body. Here we can see that oxygenated blood never flows through the heart as it goes directly to the body. Such type of single circulation is seen in fishes. Thus, the heart pumps only impure blood in the case of sharks which is a type of fish. An S-shaped heart is present in them with two chambers.

Additional information:
Let us look at the process of double circulation in our bodies. It consists of
Pulmonary circulation: The deoxygenated blood is pumped from the right ventricle which takes the blood to the lungs where it becomes oxygenated. The oxygenated blood is carried by the pulmonary vein to the left auricle/atrium of the heart. This pathway from the right ventricle to the lungs to the left atrium is known as the pulmonary circulation.
Systemic circulation: The oxygenated blood is pumped by the left ventricle into the aorta from where it is carried by a network of arteries and capillaries to the tissues of the body where it becomes deoxygenated. This deoxygenated blood is carried by the veins and vena cava and emptied into the right atrium. This is known as systemic circulation and its function is to provide nutrients and oxygen to the body and remove carbon dioxide and harmful substances from it.

So, the correct option is ‘Sharks’.

Note:
-The circulatory system is of two types known as open and closed types.
-The open circulatory system is seen in arthropods and mollusks where the blood flows into open spaces of cavities known as sinuses.
-The closed circulatory system is seen in annelids and chordates where blood flows through a closed network of blood vessels.