Question

Which of the following statements regarding small intestine are incorrect?
(i) Throughout the small intestine, there are crypts of Lieberkuhn at the base of the villi.
(ii) In duodenum, there are, in addition, small rounded
peptic glands.
(iii) The small intestine is strongly self-protective, by means of a copious production of mucus and
a mechanism for the rapid replacement of cells damaged by contact with food and digestive juices.
(iv) Each villus is richly supplied with blood capillaries only.

• A. (i) and (iv)
• B. (ii) and (iv)
• C. (i) and (iii)
• D. (iii) an (iv)

Answer 1

Answer: (B)

The surface of the gastrointestinal tract is lined by the invaginations of the epithelium which extend into the sub-mucosa.These invaginations of the intestine are called as crypts of Leiberkuhn. These crypts have specialised secretory cells called as paneth cells. They play an integral role in maintaining intestinal homeostatic balance with associated microbial flora.
The duodenum does not have peptic glands. The gastric glands are present in the stomach which contains peptic cells.
The Intestinal mucosa layer possesses goblet cells which secrets mucus and the sub-mucosa layer also contains Brunner's gland. It is a compound tubular gland present in duodenum. It secrets alkaline, mucoid fluid which contains no enzymes.
The mucosa layer of alimentary canal folds in the intestine to form villi and the villi are supplied with blood capillaries and lymph vessels as well such as lacteal lymph.