Question

(a) What is common for Cuscuta, ticks and leeches?
(b) Name the substances on which the following enzymes act in the human digestive system:
(i) Trypsin
(ii) Amylase
(iii) Pepsin
(iv) Lipase
(c) Why does absorption of digested food occur mainly in the small intestine?

Answer 1

(a) In Cuscuta, ticks and leeches, the mode of nutrition is parasitic.

(b) (i) Trypsin acts on proteins.
(ii) Amylase acts on starch.
(iii) Pepsin acts on proteins.
(iv) Lipase acts on emulsified fat.

(c) Absorption of digested food occurs mainly in the small intestine because it consist of many finger-like projections called villi that are supplied with numerous blood vessels. They provide a large surface area for the absorption of food.