The human body has an organ A which acts as a double pump. The oxygenated blood coming from the lungs through a blood vessel B enters the upper left chamber C of the double pump. When chamber C contracts, then blood goes into lower left chamber D. The contraction of chamber D forces the blood to go into a blood vessel E which supplies oxygenated blood to all the organs of the body (except the lungs). The deoxygenated blood coming out of the body organs is taken by a blood vessel F to the right upper chamber G of pumping organ. Contraction of Chamber G forces the deoxygenated blood into right lower chamber H. And finally the contraction of chamber H sends the deoxygenated blood into lungs through a blood vessel I.

(a) What is organ A ?

(b) Name the blood vessel (i) B (ii) E (iii) F, and (iv) I.

(c) What are chambers (i) C, and (i) D?

(d) What are chambers (i) G and (ii) H ?