Which of the following categories of macromolecules includes representatives that grequently serve as energy storage molecules ?

Options

A. Proteins
B. Lipids
C. Carbohydrates
D. Both lipids and carbohydrates

Explanation

To solve the question regarding which category of macromolecules includes representatives that frequently serve as energy storage molecules, we can follow these steps:

### Step 1: Understand the Categories of Macromolecules
The main categories of macromolecules include:
- Proteins
- Lipids
- Carbohydrates
- Nucleic Acids

### Step 2: Identify Energy Storage Functions
Next, we need to identify which of these macromolecules serve as energy storage:
- **Proteins**: Primarily serve as structural components and perform various functions in the body, but they are not primarily used for energy storage.
- **Lipids**: These include fats and oils, which are known for their role in energy storage. They store energy in the form of triglycerides.
- **Carbohydrates**: These include sugars and starches. Glycogen (a polysaccharide) is a form of carbohydrate that serves as a short-term energy storage in animals, while starch serves a similar purpose in plants.

### Step 3: Analyze the Options
Now, let’s analyze the options given:
1. Proteins
2. Lipids
3. Carbohydrates
4. Both lipids and carbohydrates

### Step 4: Determine the Correct Answer
From our analysis, we see that both lipids (triglycerides) and carbohydrates (glycogen and starch) serve as energy storage molecules. Therefore, the correct answer is:
**Both lipids and carbohydrates.**

### Final Answer
The category of macromolecules that includes representatives that frequently serve as energy storage molecules is **both lipids and carbohydrates**.

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