Question

glycogen structure diagram (chemical structure and highly-branched glycogen). glycogen plays an important role in regulating blood sugar. when glucose levels in blood low, glycogen is broken down by the body to provide glucose. in the muscles, glycogen also broken down to release energy to help with muscle contraction. what are the functions of glycogen? select all that apply. animals store excess sugar as glycogen. glycogen can be broken down to release glucose and increase blood sugar. glycogen provides structural support for cell walls. energy from glycogen can be used for muscle contraction.

Explanation:

• Option A: Animals (including humans) store excess glucose as glycogen in the liver and muscles, so this is correct.
• Option B: The text states "When glucose levels in blood are low, glycogen is broken down by the body to provide glucose", so this is correct.
• Option C: Glycogen is an energy - storage molecule, not a structural component of cell walls (cellulose provides structural support for plant cell walls), so this is incorrect.
• Option D: The text says "In the muscles, glycogen is also broken down to release energy to help with muscle contraction", so this is correct.

Answer:

A. Animals store excess sugar as glycogen.
B. Glycogen can be broken down to release glucose and increase blood sugar.
D. Energy from glycogen can be used for muscle contraction.