Nonetheless, it differs from keratin through its carbohydrate polysaccharide structural component. In terms of structure, it resembles cellulose. Chitin is a modified carbohydrate for containing nitrogen.
In cellulose though, the monomers are glucose units. Furthermore, chitin has an acetylamine group instead of a hydroxyl group on each monomer. This enables more opportunities of hydrogen bonding between polymers in chitin, and thereby renders increased structural strength. Removal of the acetyl COCH3 groups from chitin results in the formation of chitosan , which unlike chitin, is soluble in water. Chitin is considered as the second most abundant natural polysaccharide.
It occurs in the exoskeleton of certain insects and crustaceans. It is also a component of the cell wall in certain fungi. Other organisms that synthesize chitin are certain protist s , sponge s , coelenterates , nematode s , mollusks , and Rhizobia. In insects, chitin is synthesized chiefly in the epidermis and the midgut. Chitin precursors may be trehalose and glycogen. In insects and crustaceans that undergo molting and metamorphosis, chitin degradation and synthesis occur simultaneously and in a coordinated manner.
Chitin serves as a protective covering and mechanical support to soft-bodied organisms producing it. In insects and arthropods, chitin is a crucial component of their exoskeleton. Chitin is also present in insect body wall, gut lining, salivary glands, mouth parts, and muscle attachment points. In chitinous fungi, chitin is present rather than cellulose in their cell wall. Apart from insects, certain arachnids have also chitin in their hard outer covering.
Chitin is also present in the radula of molluscs and the beaks of cephalopods. Humans and other vertebrates do not produce chitin. As such, enzymes that degrade chitin can be used as potential fungicides as well as insecticides that target chitinous fungi and disease-causing insects.
Chitin and chitosan are used as food additive, thickener, texturizer, emulsifier, humectant, and stabilizer in confectionery, beverages, and other foods. Chitosan is regarded as generally safe by the U. Food and Drug Administration. However, individuals with allergies in crustaceans may need to avoid chitin- or chitosan-containing food. This tutorial noted some of the physical and chemical factors that provide the framework of a running water community in.. Plants in lentic habitats have features not found in terrestrial plants.
They acquired these features as they adapt to t.. Pure chitin is translucent and flexible. However, in many animals, chitin is combined with other molecules to form a composite material. For example, in mollusks and crustaceans it combines with calcium carbonate to form hard and often colorful shells. In insects, chitin is often stacked into crystals that produce iridescent colors used for biomimicry, communication, and to attract mates.
Chitin is primarily a structural material in organisms. It is the main component of fungal cell walls. It forms the exoskeletons of insects and crustaceans. It forms the radulae teeth of mollusks and the beaks of cephalopods. Chitin also occurs in vertebrates. Fish scales and some amphibian scales contain chitin. Plants have multiple immune receptors to chitin and its degradation products. When these receptors are activated in plants jasmonate hormones are released that initiate an immune response.
This is one way plants defend themselves against insect pests. In agriculture, chitin may be used to boost plant defenses against disease and as a fertilizer. Humans and other mammals do not produce chitin. However, they have an enzyme called chitinase that degrades it. Chitinase is present in human gastric juice, so chitin is digestible.
Chitin and its degradation products are sensed in the skin, lungs, and digestive tract, initiating an immune response and potentially conferring protection against parasites. Allergies to dust mites and shellfish are often due to a chitin allergy. Because they stimulate an immune response, chitin and chitosan may be used as vaccine adjuvants.
Chitin may have applications in medicine as a component of bandages or for surgical thread. Chitin is used in paper manufacturing as a strengthener and sizing agent. Chitin is used as a food additive to improve flavor and as an emulsifier. It is sold as a supplement as an anti-inflammatory agent, to reduce cholesterol, support weight loss, and control blood pressure.
Chitosan may be used to make biodegradable plastic. Actively scan device characteristics for identification. Use precise geolocation data. Select personalised content. Create a personalised content profile. Measure ad performance. Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights.
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