The chemical and physical properties of Amino acids are of essentially because of :

Options

A. Amino group
B. Carboxyl group
C. Functional - R group
D. All of these

Answer

To solve the question regarding the chemical and physical properties of amino acids, we need to analyze the components of an amino acid and how they contribute to its properties.

### Step-by-Step Solution:

1. **Identify the Structure of Amino Acids**:
- Amino acids have a basic structure that includes an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom (H), and a variable side chain known as the R group.

2. **Understand the Role of Each Group**:
- **Amino Group**: This group is responsible for the basic properties of amino acids. It can accept protons, which contributes to the overall charge and reactivity of the amino acid.
- **Carboxyl Group**: This group can donate protons, giving amino acids their acidic properties. It also plays a role in the formation of peptide bonds during protein synthesis.
- **R Group (Functional Group)**: The R group varies between different amino acids and determines their unique properties. It influences the polarity, charge, and overall behavior of the amino acid in biological systems.

3. **Consider the Interactions Between These Groups**:
- The interactions between the amino group, carboxyl group, and R group contribute to the amino acid's solubility, reactivity, and ability to form zwitterions (molecules with both positive and negative charges).

4. **Conclusion**:
- Since all three groups (amino, carboxyl, and functional R group) play significant roles in determining the chemical and physical properties of amino acids, the correct answer to the question is "all of these."

### Final Answer:
The chemical and physical properties of amino acids are essentially because of **all of these**: amino group, carboxyl group, and functional R group.

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