Which of the following is a similarity between lipids and carbohydrates?

• A. Both readily dissolve in water due to their polar nature.
• B. Both serve as important sources of energy for cells.
• C. Both contain nitrogen as a major component.
• D. Both are composed of amino acids.

Answer: (B)

Verified step by step guidance

1. Understand the question: The problem is asking for a similarity between lipids and carbohydrates, focusing on their biological roles or chemical properties.
2. Analyze the first option: 'Both readily dissolve in water due to their polar nature.' Lipids are generally nonpolar and hydrophobic, meaning they do not readily dissolve in water. Carbohydrates, on the other hand, are polar and hydrophilic, so this option is incorrect.
3. Analyze the second option: 'Both serve as important sources of energy for cells.' Lipids and carbohydrates are both used by cells as energy sources. Carbohydrates are the primary energy source, while lipids provide long-term energy storage. This option is correct.
4. Analyze the third option: 'Both contain nitrogen as a major component.' Nitrogen is not a major component of lipids or carbohydrates. It is primarily found in proteins and nucleic acids, so this option is incorrect.
5. Analyze the fourth option: 'Both are composed of amino acids.' Amino acids are the building blocks of proteins, not lipids or carbohydrates. This option is incorrect.