Question

Chitin is polymer of
A. N-acetyl muramic acid
B. N-acetyl gluconic acid
C. N-acetyl glucosamine
D. None of the above

Answer 1

Hint: Chitin is a fibrous substance consisting of polysaccharides.
It is the major component of the exoskeleton of arthropods and the cell walls of fungi.
It functions as the scaffold materials that support the cuticles of the epidermis and trachea.

Complete answer:
Polymer: It is a substance composed of very large molecules or macromolecules that is further composed of many repeating subunits.
Polymers are of two types:
1. Synthetic polymers
2. Natural polymers
Chitin is a long-chain polymer of N-acetylglucosamine which is a derivative of glucose.
This polysaccharide is a main component of cell walls in fungi and in the exoskeletons of arthropods, such as crustaceans and insects, the radulae of molluscs, cephalopod beaks, and the scales of fish and lissamphibians.
The structure of chitin is comparable to another polysaccharide such as cellulose, forming crystalline nanofibrils or whiskers.
Chitin has proved useful for several
1. Medicinal
2. Industrial
3. Biotechnological purposes.
Humans and other mammals have chitinase and chitinase-like proteins that help in degradation of chitin.
They also possess several immune receptors that can recognize chitin and its degradation products in a pathogen-associated molecular pattern initiating an immune response.
Chitin is sensed mostly in the lungs or gastrointestinal tract where it can activate the innate immune system through eosinophils or macrophages, as well as an adaptive immune response through T helper cells.
According to in vitro studies, chitin is sensed by receptors, such as FIBCD1, KLRB1, REG3G, Toll-like receptor 2, CLEC7A, and mannose receptors.

So, the correct option is option C. N-acetyl glucosamine.

Note: The immune response can sometimes clear the chitin and its associated organism, but sometimes the immune response is pathological and becomes an allergy; allergy to house dust mites is thought to be driven by a response to chitin.
The structure of chitin is determined by Albert Hofmann.