Question

The longest part of the alimentary canal is

• A. Esophagus
• B. Large intestine
• C. Small intestine
• D. Stomach

Answer 1

The correct option is C

Small intestine

The correct option is C.

Explanations for the correct option:

1. The alimentary canal refers to the muscular tube that extends from the mouth to the anus.
2. It includes the mouth, pharynx, esophagus, stomach, small intestine, large intestine, and anus.
3. The longest part of the alimentary canal is the small intestine and is 22 to 25 feet in length.
4. It begins at the pylorus and terminates at the ileocecal valve and is divided into duodenum, jejunum, and ileum.
5. The partially digested food that reaches the small intestine is absorbed by the duodenum.
6. It has finger-like projections known as villi on its surface that absorb the digested nutrients.
7. The undigested and unabsorbed food particles are then passed onto the large intestine.

Explanations for the incorrect options:

Option A:

1. The esophagus is the muscular tube that transports food from the mouth to the stomach and is about 10 inches long.
2. The muscles in it propel food towards the stomach by peristalsis.

Option B:

1. The large intestine is the last section of the gastrointestinal tract and absorbs water and salts from undigested food. It is almost five feet long.
2. It is divided into four sections - the cecum, colon, rectum, and anal canal.

Option D:

1. The stomach receives food from the esophagus and conducts food digestion.
2. It is about 12 inches long.
3. It is divided into three parts - the duodenum, jejunum, and ileum.
4. The absorption of vitamins, minerals, carbohydrates, fats, and proteins occurs here.

Final answer: The longest part of the alimentary canal is the small intestine.