A fatty acid or amino acid is called essential when

Options

A. cell is unable to synthesize it on its own
B. cell requires it badly and so make it on its own
C. cell badly needs it but does not make it on its own.
D. cell needs it and gets it from adjacent cells

Answer

To determine when a fatty acid or amino acid is called essential, we can follow these steps:

### Step-by-Step Solution:

1. **Definition of Essential Fatty Acids and Amino Acids**:
- A fatty acid or amino acid is termed "essential" when it is necessary for the body’s biological functions but cannot be synthesized by the body itself.

2. **Requirement for Biological Processes**:
- These essential compounds are crucial for various biological processes, such as building proteins, producing hormones, and maintaining cell structure.

3. **Synthesis in the Body**:
- Essential fatty acids and amino acids must be obtained from the diet because the body lacks the ability to produce them. This inability to synthesize them is what classifies them as "essential."

4. **Examples of Essential Fatty Acids**:
- There are two primary essential fatty acids:
- Omega-3 fatty acid (Alpha-linolenic acid)
- Omega-6 fatty acid (Linoleic acid)

5. **Examples of Essential Amino Acids**:
- In humans, there are nine essential amino acids:
- Histidine
- Leucine
- Lysine
- Isoleucine
- Phenylalanine
- Valine
- Methionine
- Tryptophan
- Threonine

6. **Conclusion**:
- Therefore, a fatty acid or amino acid is called essential when the body requires it for biological processes but cannot synthesize it on its own.

### Final Answer:
A fatty acid or amino acid is called essential when the cell badly needs it but does not make it on its own.

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