Which type of organic compound generally stores the most chemical energy per $g$, and which stores the least?

• A. Carbohydrates store the most energy, while nucleic acids store the least.
• B. Lipids store the most energy, while carbohydrates store the least.
• C. Nucleic acids store the most energy, while proteins store the least.
• D. Proteins store the most energy, while lipids store the least.

Answer: (B)

Verified step by step guidance

1. Step 1: Understand that the question asks about the amount of chemical energy stored per gram in different types of organic compounds: lipids, carbohydrates, proteins, and nucleic acids.
2. Step 2: Recall that chemical energy storage is related to the molecular structure and the types of bonds present. More reduced compounds (with more C-H bonds) generally store more energy.
3. Step 3: Recognize that lipids are highly reduced molecules with many C-H bonds, making them energy-dense and thus storing the most energy per gram.
4. Step 4: Carbohydrates are more oxidized compared to lipids, containing more oxygen atoms and fewer C-H bonds, so they store less energy per gram than lipids.
5. Step 5: Nucleic acids and proteins generally store even less energy per gram than carbohydrates because of their structures and functional groups, with nucleic acids typically storing the least.