When a pers

(a) (i) Salivary glands (A) present in the mouth and secrete saliva.

(ii) Salivary glands(A) secrete saliva (B) which contains an enzyme called salivary amylase (C).

(b) D is Oesophagus. Oesophagus is a long, thin and muscular tube that connects the throat (pharynx) to the stomach.

(c) Peristaltic movement (E) is a wave of contraction and expansion which occurs in the alimentary canal and helps to push the food forward.

(d) (i) Hydrochloric acid (ii) Mucus (iii) Enzyme pepsin

The stomach wall secretes gastric juice which contains three substances: Hydrochloric acid (F), the enzyme pepsin (G) and mucus (H).