Solution:

• Digestion starts at mouth .
• Stomach – Food reaches the stomach from the mouth through the oesophagus . It is the wave like movement of the oesophagus which enables this . This is called peristalsis. Due to the movement of the stomach wall , food is rendered paste like inside the stomach . The digestive enzymes produced by the stomach digests food chemically too .
• Small intestine – small intestine is about six metre long . Digestion of food is completed here . The nutrients in the digested food are absorbed into the blood .
• Large intestine – Large intestine is the broader intestine following small intestine and is about one and a half metre long . The absorption of water containing minerals and salts takes place here . What remains after that is the faeces . It is stored in the rectum and expelled through the anus .