Where does digestion of fat take place in our body?

What are the final products produced after the digestion of carbohydrates, proteins, and fats?

$(a)$ Draw a sectional view of the human heart and label on it Aorta,Pulmonary arteries,Vena cava,Left ventricle.
$(b)$ Why is double circulation of blood necessary in human beings?

State in brief the function of:
$(a)$ Renal artery
$(b)$ Kidney
$(c)$ Ureter
$(d)$ Urinary bladder

What is the functional difference between the four chambers of the heart?

Match Group $(A)$ with Group $(B)$:

Group $(A)$	Group $(B)$
$(a)$ Autotrophic nutrition	$(i)$ Leech
$(b)$ Heterotrophic nutrition	$(ii)$ Paramecium
$(c)$ Parasitic nutrition	$(iii)$ Deer
$(d)$ Digestion in food vacuoles	$(iv)$ Green plant