Which of the following carbohydrates primarily functions as a long-term energy storage molecule in animals?

• A. Cellulose
• B. Glycogen
• C. Glucose
• D. Lactose

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the role of carbohydrates in biological systems. Carbohydrates serve various functions, including energy storage, structural support, and as components of cellular communication.
2. Step 2: Review the specific functions of the given carbohydrates: Cellulose is a structural carbohydrate found in plants, Glucose is a simple sugar used for immediate energy, Lactose is a disaccharide found in milk, and Glycogen is a polysaccharide used for energy storage in animals.
3. Step 3: Recall that animals store energy in the form of glycogen, which is a highly branched polymer of glucose. Glycogen is stored primarily in the liver and muscles and can be broken down into glucose when energy is needed.
4. Step 4: Compare the options provided in the question. Glycogen is the only carbohydrate listed that functions as a long-term energy storage molecule in animals.
5. Step 5: Conclude that the correct answer is Glycogen, as it matches the description of a long-term energy storage molecule in animals.