The largest artery is the aorta and the largest vein is the vena cava.

Explain the role of bile juice in digesting food.

$(a)$ What is the role of mucus in the stomach?
$(b)$ How is the exit of food from the stomach regulated?
$(c)$ Where does food enter from the stomach?

Kidneys are located in the thoracic cavity, one on either side of the backbone.

Name the following with reference to the alimentary canal:
$(a)$ $(i)$ The largest gland.
$(ii)$ The gland that secretes digestive enzymes as well as hormones.
$(iii)$ The part where digested food is absorbed.
$(b)$ What are villi? Mention their function.

$(a)$ Draw the structure of a nephron and label the following on it: Glomerulus,Bowman's capsule,Renal artery,Collecting duct.
$(b)$ What happens to glucose that enters the nephron along with the filtrate?