The correct sequence of the parts of small intestine is:

Q: The correct sequence of the parts of small intestine is:

The correct sequence of the parts of small intestine is:

Question

Accepted Answer

The correct option is (1):
The correct anatomical sequence of the parts of the human small intestine is the Duodenum, followed by the Jejunum, and finally the Illeum. This order is non-negotiable for the proper functioning of the digestive system. The Duodenum is the first and shortest section, a C-shaped tube that connects to the stomach and is the critical site for mixing the chyme with bile from the liver and digestive enzymes from the pancreas. Following the Duodenum is the Jejunum, which is the middle section and constitutes roughly two-fifths of the remaining small intestine length; its primary role is the rapid absorption of digested carbohydrates and proteins. The final and longest part is the Illeum, which connects to the large intestine at the ileocecal valve and is responsible for absorbing specific remaining nutrients, such as Vitamin B12 and bile salts, before waste is passed on.

The incorrect option is (2):
The sequence Jejunum, Illeum, Duodenum is anatomically incorrect because it places the middle and end segments before the beginning segment. The Duodenum must always be the first part, as it receives chyme directly from the stomach. Starting the digestive sequence with the Jejunum is a complete reversal of the organ's function and location within the abdominal cavity.

The incorrect option is (3):
The order Illeum, Duodenum, Jejunum is incorrect. The Illeum is the final segment of the small intestine, responsible for passing digested material to the large intestine, not for receiving material from the stomach. Placing it first in the sequence violates the natural flow of food through the digestive tract and prevents proper digestion and absorption.

The incorrect option is (4):
The sequence Duodenum, Illeum, Jejunum is incorrect because it swaps the positions of the Jejunum and the Illeum. While the Duodenum is correctly placed first, the Jejunum must always precede the Illeum. The Jejunum is strategically positioned for maximum general nutrient absorption, which should happen before the final, specialized absorption duties of the Illeum.