Question

Compound starch grains are present in
A. Potato
B. Rice
C. Oat
D. All of the above

Answer 1

Starch is formed by a-1, 4 linkages between two glucose units. Starch is broken down during digestion. It acts as food material for plant cells. Starch or amylum is a polymeric carbohydrate that consists of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants as energy storage.

Complete answer:

Option A - Potato
The potato is a root vegetable inhabitant of the Americas. It is a starchy tuber of the plant Solanum tuberosum and family Solanaceae. In potatoes, Oval and eccentric starch grains are present which are stored to support the plant during scarcity. Starch grain owns a central proteinaceous area called helium around which the starch is deposited as an oval eccentric layer in potato. The potato is scarcely eaten raw because raw potato starch is poorly digested by humans.

Option B - Rice
Starch grains in rice include the mixture of alpha-amylase and amylopectin. The size of rice grains varies similarly to potato starch- 15-100 µm, maize starch 5-25 µm, and rice starch 3-8 µm.

Option C - Oats
Oat starch contains about 25-30% amylases. They are a class of hydrolases that can specifically cleave the O-glycosidic bonds in starch.

Hence, the correct answer is option (D).

Note: Starch refers to long chains of sugar glucose joined together. Starches, previously known as complex carbohydrates occur naturally in a large range of foods. These include nutrient-rich foods like root vegetables, legumes, cracked wheat, brown rice, pearl barley, quinoa, and oats.