Question

A storage protein is
(a)Keratin
(b)Collagen
(c)Haemoglobin
(d)Glutelin/Globulin

Answer 1

Hint: Storage proteins are the biological reserves of ions and amino acids that are used by the organisms. They are seen in plant seeds, egg whites, milk, etc. One of these storage proteins is seen in the seeds of certain grass species.

Complete answer:
Glutelin is a class of prolamin proteins that are seen in the endosperm of certain seeds of the grass family. They are a major component of the protein composite that is collectively referred to as gluten.
This class of storage proteins was originally differentiated from the prolamins by Thomas Burr Osborne based on its low solubility. Modern analysis however considers glutelin as a low-solubility subclass of the prolamins.

Additional Information: -Glutelin is soluble in dilute bases or acids, detergents, or reducing agents. They are also rich in hydrophobic amino acids, such as phenylalanine, valine, tyrosine, leucine, and proline.
-There are two kinds of glutelin: High-molecular-weight (HMW) and Low-molecular-weight (LMW) glutelin in most of the grass species. These proteins cross-link with each other and other proteins via disulphide bonds.
-Keratin is a structural protein that is found in hairs, nails, horns, hooves, claws, etc, and is also found in the outer layer of human skin.
-Collagen is also a structural protein that forms the building blocks of the entire body.
-Haemoglobin is a blood protein that is formed of two parts, haem, and globin. It helps in oxygen transport and gaseous exchange.
So, the correct answer is, “Glutelin/Globulin”.

Note: -Glutenin is the commonest form of glutelin that is found in wheat and is responsible for some of the refined properties present in baked bread wheat.
-Glutelin is the primary energy storage form in the endosperms of rice.
-An HMW glutelin (glutenin) of the grass tribe Triticeae which includes wheat and oats has been implicated as the sensitizing agent for coeliac disease in susceptible individuals. In such individuals, a gluten-free diet is advised.