Arachidonic acid ha s a carboxyl group attached to an R group. This R group contain:-

Options

A. 16 carbons
B. 15 carbons
C. 20 carbons
D. 19 carbons

Answer

To solve the question regarding the R group of arachidonic acid, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Arachidonic Acid**:
- Arachidonic acid is a type of fatty acid. Fatty acids typically consist of a long hydrocarbon chain (the R group) and a carboxyl group (-COOH).

2. **Identifying the Structure**:
- The structure of arachidonic acid includes a carboxyl group attached to a long hydrocarbon chain (the R group).

3. **Counting Carbons**:
- Arachidonic acid has a total of 20 carbon atoms in its structure. This includes the carbon atom from the carboxyl group.

4. **Calculating the R Group**:
- Since the carboxyl group contributes 1 carbon atom, we subtract this from the total number of carbons to find the number of carbons in the R group.
- Total carbons in arachidonic acid = 20
- Carbons in the carboxyl group = 1
- Therefore, Carbons in the R group = 20 - 1 = 19

5. **Conclusion**:
- The R group of arachidonic acid contains 19 carbon atoms.

### Final Answer:
The R group of arachidonic acid contains **19 carbons**.

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