Given diagram is a schematic representation of the circulatory system in humans. Study the same and answer the questions that follow :

(a) Label the parts 1 and 4 indicated in the diagram.
(b) Which of the above mentioned number is the thickest artery? Also write its name.
(c) Mention the number and chamber of the heart which has the thickest muscular wall.
(d) Which of the above numbers/structures has the maximum number of blood capillaries?
(e) Draw neat and labelled diagrams of the transverse section of vena cava and the part numbered as 3. Make sure to show the structural differences between these two in the diagram.
(a) Parts 1 and 4 are:
1 → Right Auricle
4 → body parts
(b) 3, Aorta
(c) 2, Left ventricle
(d) Lungs
(e) Labelled diagrams of the transverse section of vena cava and aorta showing their structural differences are given below:
