Question

Glycosidic linkage present between adjacent glucose units of starch or glycogen is generally-
A. \[\beta 1 - {\text{ }}4\]
B. \[\alpha 1 - {\text{ }}4\]
C. \[\alpha 2 - 1\]
D. \[\beta 2 - 1\]

Answer 1

Hint: A glycosidic linkage, also known as a glycosidic bond, is a form of covalent bond that connects a carbohydrate molecule to another group, which could be another carbohydrate or not. A glycosidic bond is formed between the hemiacetal or hemiketal group of a saccharide of some compound such as an alcohol. Examples will be- Hemiacetal and Hemiketal are formed by glycosidic linkage.

Complete Explanation:
Option A \[\beta 1 - {\text{ }}4\]: Glycosidic linkage present between adjacent glucose units of starch or glycogen is not Beta linkage as $4$ carbon is linked in the side chain that is true but the beta carbon is not linked.
So, option A is not correct.
Option B \[\alpha 1 - {\text{ }}4\]: Glycosidic linkage present between adjacent glucose units of starch or glycogen is generally alpha \[1 - 4\] linkage. Alpha carbon of the first unit of glucose is linked to the $4$ carbon of another unit of glucose is linked to the $4$ carbon of another unit of glucose of the side chain.
So, option B is correct
Option C \[\alpha 2 - 1\]: Most of the glucose units in glycogen are linked by alpha \[1\],\[4\] glycosidic bonds. The branches are formed by alpha \[1\],\[6\] glycosidic bonds, present about once in \[10\] units. Hence, this is not the correct answer.
Option C is not correct.
Option D \[\beta 2 - 1\]: Glycosidic linkage present between glucose and starch units are generally bonded by alpha carbon chain not the beta carbon chain. And it is linked by $4$ carbon units.
Option D is not correct.

Hence, Option B is the correct answer.

b>Note:
Hence it is discussed that alpha \[1\],\[4\] glycosidic linkage is present between the respective glucose and starch units. In humans both glucose and starch both are stored in glycogen. Glucose is the simplest form of carbohydrate so; it gets easily absorbed by the digestive tract of the organism. Whereas starch is a complex form of glucose it takes time to get absorbed.