State the function of the following in the alimentary canal:
$(i)$ Liver $(ii)$ Gall bladder $(iii)$ Villi.

(N/A) Liver: Produces bile juice. Bile salts present in it emulsify large fat globules into smaller ones,facilitating digestion. It also stores excess glucose in the form of glycogen.
Gall bladder: Stores and concentrates the bile juice produced by the liver until it is needed for digestion in the small intestine.
Villi: These are numerous finger-like projections present on the inner lining of the small intestine. They increase the surface area for the absorption of digested food. The villi are richly supplied with blood vessels that transport the absorbed nutrients to every cell of the body.