Which molecule is known for storing long-term energy?

• A. Glucose
• B. Triglycerides
• C. Glycogen
• D. Proteins

Answer: (B)

Triglycerides are the primary molecules responsible for storing long-term energy in the body. They consist of three fatty acids attached to a glycerol backbone, making them efficient for energy storage due to their high caloric density. When energy is needed, triglycerides can be broken down through lipolysis into glycerol and free fatty acids, which can then be utilized by the body for energy or converted into usable forms like ATP.

In comparison, glucose is a simple sugar that provides quick energy but does not serve as a long-term storage form. Glycogen, while it is also a storage form of energy, is primarily used for short-term energy needs; it is a polysaccharide stored in the liver and muscles for rapid release when glucose is needed. Proteins can be used for energy, but their main functions in the body are structural and functional, and they are not primarily used for energy storage. Given these roles, triglycerides stand out as the most significant molecule for long-term energy storage.