In vertebrates glycogen is stored chiefly in

Options

A. heart and blood
B. spleen and stomach
C. bones and lymph
D. liver and muscles

Answer

**Step-by-Step Solution:**

1. **Understanding Glycogen**: Glycogen is a polysaccharide that serves as a form of energy storage in animals. It is composed of glucose units and is primarily utilized when the body requires energy.

2. **Identifying Storage Locations**: In vertebrates, glycogen is chiefly stored in two main locations: the liver and muscle tissues. These are the primary sites where glycogen is synthesized and stored.

3. **Role of the Liver**: The liver plays a crucial role in maintaining blood glucose levels. It stores glycogen and can convert it back into glucose when the body needs energy, particularly between meals or during fasting.

4. **Role of Muscle Tissue**: Muscle cells also store glycogen, which is used primarily for energy during physical activity. When muscles contract, they break down glycogen to glucose to fuel their activity.

5. **Conclusion**: Therefore, the correct answer to the question of where glycogen is chiefly stored in vertebrates is the liver and muscle tissues.

**Final Answer**: In vertebrates, glycogen is chiefly stored in the liver and muscle tissues.

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