Question

Identify the polysaccharide with $\beta $- glycosidic bond
A. Starch
B. Glycogen
C. Sucrose
D. Cellulose

Answer 1

Hint: There are polysaccharides in our body which will break to give the energy in the form of ATP. They can be homopolymers that are made of the same units or heteropolymers that are made of different units. They are the long chains having bondings in between them.

Complete answer:
We need glucose molecules or carbon sources to gain energy. There are polysaccharides which can be homo or hetero that have the chains of sugars.
Let us learn about the options.
Option A: Starch: It is a homopolysaccharide made of D-glucose. It has 2 polymers-amylase and amylopectin. In amylase, the D-glucose is connected to the alpha 1,4 linkages. In the amylopectin, the alpha 1,4 linkages are joined to the alpha1,6 linkages.
Option B: Glycogen: It is a homopolysaccharide but is different from the starch as glycogen is highly branched but has the same bondings.
Option C: Sucrose: It is the polymer of glucose having residues linked to each other by alpha 1,4 glycosidic linkages.
Option D: Celulose: It is a homopolysaccharide, it is linear. It has D-glucose units linked to each other by beta 1,4 glycosidic bonds.

So the answer is option D: Cellulose.

Note: It is an organic compound forming the structural component of the cell wall of plants. Humans cannot digest cellulose, only the ruminants can. It is a source of fibre. Cellulose is used to make paper and clothes. It gives rigidity to the plant cell. It protects the interiors of the plant cells. Peas, cabbage etc. have cellulose in them.