Which of the following is the major structural difference between $\mathrm{glycogen}$ and $\mathrm{amylopectin}$?

• A. $\mathrm{Glycogen}$ has more frequent branching than $\mathrm{amylopectin}$.
• B. $\mathrm{Amylopectin}$ is composed of glucose units linked by $\beta$-glycosidic bonds.
• C. $\mathrm{Amylopectin}$ contains $\mathrm{fructose}$ units instead of $\mathrm{glucose}$.
• D. $\mathrm{Glycogen}$ is a linear polymer of $\mathrm{glucose}$.

Answer: (A)

Verified step by step guidance

1. Begin by understanding the basic structure of both glycogen and amylopectin. Both are polysaccharides composed of glucose units, but they differ in their branching patterns.
2. Glycogen is known for its highly branched structure. It consists of α(1→4) linked glucose units with α(1→6) branches occurring approximately every 8-12 glucose units.
3. Amylopectin, on the other hand, is a component of starch and has a less frequent branching pattern compared to glycogen. It also consists of α(1→4) linked glucose units, but its α(1→6) branches occur approximately every 24-30 glucose units.
4. Clarify the misconception: Amylopectin is composed of glucose units linked by α-glycosidic bonds, not β-glycosidic bonds. Additionally, amylopectin does not contain fructose units; it is solely composed of glucose.
5. Conclude by comparing the branching frequency: Glycogen has more frequent branching than amylopectin, which is the major structural difference between the two polysaccharides.