Question

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

Explanation:

1. For "Glycogen can be broken down to release glucose and increase blood sugar": The text says when blood glucose is low, glycogen is broken down to provide glucose, so this is correct.
2. For "Animals store excess sugar as glycogen": Glycogen is an energy - storage molecule in animals, so they store excess sugar as glycogen, this is correct.
3. For "Glycogen provides structural support for cell walls": Cell walls of plants have cellulose for structural support, and glycogen is for energy storage, not structural support in cell walls, so this is incorrect.
4. For "Energy from glycogen can be used for muscle contraction": The text states that in muscles, glycogen is broken down to release energy for muscle contraction, so this is correct.

Answer:

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