Question

8.0 List the structures and organs involved in ingestion of food until the leftover of undigested food is eliminated. List in order and indicate where chemical and physical breakdown and absorption of nutrients take place.

Answer 1

The complete pathway that the ingested food takes is known as gastrointestinal tract. It begins from the mouth and ends at anal canal.

The order of organs is as follows:

- Oral cavity/ mouth : site where physical breakdown occurs by chewing.

- Oropharynx

- Esophagus

- Stomach : site where some of physical and chemical breakdown occurs.

- Small intestine (which includes the following:)

a) Duodenum

b) Jejunum

c) Ileum: site for absorption of most of the nutrients.

- Large intestine (which includes:) - site of absorption of water and salts.

a) Caecum

b) Ascending colon

c) Transverse colon

d) Descending colon

- Rectum

- Anal canal