Which one of the following will be largely different in various animal species?

Options

A. Carbohydrates
B. Fats
C. Proteins
D. Enzymes

Explanation

To answer the question "Which one of the following will be largely different in various animal species?" we will analyze the options provided: carbohydrates, fats, proteins, and enzymes.

### Step-by-Step Solution:

1. **Understanding the Options**:
- **Carbohydrates**: These are organic compounds made of carbon, hydrogen, and oxygen. While the types of carbohydrates can vary, they generally serve similar functions across species.
- **Fats**: Also known as lipids, these molecules are primarily used for energy storage and insulation. Similar types of fats are found in many species, although their proportions may vary.
- **Proteins**: Proteins are made up of amino acids and are essential for various biological functions. They are polymers of amino acids, and the sequence and composition of these amino acids can vary significantly among different species.
- **Enzymes**: Enzymes are specialized proteins that catalyze biochemical reactions. While they are proteins, the specific enzymes present can vary, but they are still a subset of proteins.

2. **Focus on Proteins**:
- Proteins are composed of amino acids, and the structure of a protein is determined by the sequence of these amino acids. Each amino acid has a unique side chain (R group) that can differ from one amino acid to another.
- The variability in the R groups of amino acids means that proteins can have vastly different structures and functions in different species. This variability is crucial for the adaptation and functionality of proteins in various organisms.

3. **Conclusion**:
- Given that proteins can vary greatly due to the differences in their amino acid composition and structure, they are the biomolecules that will be largely different in various animal species. Therefore, the correct answer is **proteins**.

### Final Answer:
The correct answer is **proteins**.

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