Question

Which of these produces carrageenan?
A. Green Algae
B. Blue green algae
C. Red algae
D. Brown algae

Answer 1

Hint: It is also called Irish moss and is mostly found in Ireland. The thallus of this algae is very fine and present in large amounts in branch patterns..

Complete answer:
Algae are eukaryotic organisms with different chemical components in their cell wall like polysaccharides, glycoproteins such as carrageenan, cellulose, and agar. The cell wall of algae is very diverse as an assembly of polymer similar to cellulose, pectin. Algae contains complex polysaccharides that form multilayer fibrillar cell walls. Based on the colour or pigments algae are classified as: 1) Chlorophyceae: It is also called green algae due to abundance of chlorophyll a and b present. The reserve food material is starch composed of amylose and amylopectin. Example: Spirogyra 2) Phaeophyceae: also called as brown algae due to the presence of fucoxanthin. Example-Laminaria 3) Rhodophyceae: commonly known as red algae because of the predominance of red pigment called phycoerythrin. The cell wall of red algae contains mucopolysaccharides like carrageenan. Gelidium is an example of red algae.
Carrageenan is a polysaccharide which is extracted from seaweeds like red edible seaweeds which is used as a thickening, gelling and stabilizing agent. It is obtained from the cell wall of Chondrus crispus (Irish moss) which is a red algae found near the sea shores of the Northern Atlantic. It is also used as stabilization of emulsions in paints, cosmetics and in the alcohol and sugar industry.

Hence, the correct answer is option (C).

Note: Mucopolysaccharides is a long chain of polymer with the repeating units of amino acids linked with polysaccharide. They can easily bind and hold with water. Irish moss contains anti-viral properties. Commonly used to cure respiratory diseases in Ireland.