Which type of lipid is primarily responsible for long-term energy storage in animals?

• A. Steroids
• B. Phospholipids
• C. Triglycerides
• D. Waxes

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the role of lipids in biological systems. Lipids are a diverse group of molecules that include fats, oils, phospholipids, steroids, and waxes. They serve various functions such as energy storage, structural components of cell membranes, and signaling molecules.
2. Step 2: Recall the primary function of triglycerides. Triglycerides are a type of lipid composed of one glycerol molecule bonded to three fatty acid chains. Their main role is long-term energy storage in animals because they are highly efficient at storing energy due to their dense structure.
3. Step 3: Compare the functions of other lipid types mentioned in the problem. Steroids are involved in signaling and structural roles (e.g., cholesterol in membranes), phospholipids form the bilayer of cell membranes, and waxes provide protective coatings but are not primarily used for energy storage.
4. Step 4: Recognize why triglycerides are the correct answer. Triglycerides are stored in adipose tissue and can be broken down into glycerol and fatty acids during periods of energy demand, making them the primary lipid for long-term energy storage in animals.
5. Step 5: Conclude that while other lipids have important biological roles, triglycerides are specifically adapted for energy storage due to their chemical structure and storage capacity.