Question 9

Which part of the digestive canal is involved in:
(i) absorption of food .
(ii) chewing of food .
(iii) killing of bacteria .
(iv) complete digestion of food .
(v) formation of faeces .

Answer

i) Small Intestine

The digestion of fats starts in the stomach and completes or ends in the small intestine. Small intestine secretes bile, pancreatic juice and intestinal juice. They all contains fat digesting enzymes.

ii) Buccal Cavity (Mouth)

The entire process of digestion starts in our mouth, with churning. When we chew food, it gets broken down complex large pieces into smaller pieces which are easier to digest. When mixed with saliva which secretes salivary amylase, chewing process allows to extract the greatest possible amount of nutrients from the food we eat.

iii) Stomach

Antibiotics are present to kill the bacteria or antigens/ pathogens in our body, such as amoxicillin, clarithromycin (Biaxin), metronidazole (Flagyl), tetracycline (Sumycin), or tinidazole (Tindamax). Drugs which reduce the amount of acid in our stomach by blocking the tiny pumps that produce it.

iv) Small Intestine

Digestion of food completes in small intestine. The partially digested food is absorbed by the duodenum of the small intestine with the digestive juices from the liver, pancreas and its own walls.

v) Large Intestine

The large intestine consists of 75% water, fats and proteinaceous substance. Water from the undigested food is absorbed as the waste material. It takes several hours for food to travel and enters into the large intestine via the digestive tract. It occurs when fluid is in excess amount that is absorbed by the colon. As part of the digestion process, or due to fluid intake, food is mixed with large quantity of water. The colon absorbs the water and leaves the remaining materials as a semisolid mixture.