Question

Enteroendocrine glands are present in
A. Stomach
B. Intestine
C. Oesophagus
D. Both A and B

Answer 1

The specialized cells or glands which are present in the gastrointestinal tract and pancreas with endocrine function are known as enteroendocrine glands or enteroendocrine cells. In response to various types of stimuli, these cells produce gastrointestinal hormones or peptides and release them into the bloodstream for systemic effect and diffuse them as local messengers or transmit them to the enteric nervous system which activates the nervous responses.

Complete answer:
Option A) Stomach: The muscular organ located on the left side of the upper abdomen is called the stomach. The enteroendocrine cells are scattered along the epithelial layer gastro-intestinal tract from the stomach to the rectum which responds to an ingested meal by secreting various gut hormones. These hormones play a key role in the coordination of food digestion and absorption.
Hence option A is correct.
Option B) Intestine: Long, continuous tube which runs from the stomach to anus is known as the intestine. Enteroendocrine cells or glands are also present in the intestine. These cells respond to nutrients by producing more than twenty peptides within the intestine. These cells release an array of peptide hormones which acts locally on nerve endings and cells in the intestinal lining depending on their location in the gut.
Hence option B is also correct.
Option C) Oesophagus: A muscular tube which connects the mouth to the stomach is called the oesophagus. The enteroendocrine glands or cells are not present in oesophagus.
Hence option C is not correct.
Option D) Both A and B: Since both options A and B are correct.
So, option D is the right answer.

Hence, Option D) Both A and B are correct answers.

Note:
Aside from nutrient sensing, the enteroendocrine cells or glands can also recognize and react to pathogens as a result of toll-like receptor expression and microorganisms in the intestine. These cells supply hormones and cytokines on detecting pathogens and microbes to the nearby immune cells. The immune cells possess many peptide hormone receptors which can directly modulate the immune response.