What is the total number of acidic amino acids found in human proteins?

Answer

To determine the total number of acidic amino acids found in human proteins, we can follow these steps:

### Step 1: Understand the Classification of Amino Acids
Amino acids are classified into three categories: neutral, acidic, and basic. This classification is based on the functional groups present in their structure.

### Step 2: Identify Acidic Amino Acids
Acidic amino acids are characterized by having two carboxyl (COOH) groups and one amino (NH2) group. In total, there are 20 standard amino acids that are involved in protein synthesis.

### Step 3: List the Acidic Amino Acids
The two acidic amino acids that are commonly found in human proteins are:
1. Aspartic acid (Asp)
2. Glutamic acid (Glu)

### Step 4: Confirm the Structures
- **Aspartic Acid (Asp)**: Its structure includes one NH2 group and two COOH groups.
- **Glutamic Acid (Glu)**: Similar to aspartic acid, it has one NH2 group and two COOH groups.

### Step 5: Count the Total Number of Acidic Amino Acids
From the information gathered, we conclude that there are a total of **2 acidic amino acids** present in human proteins.

### Final Answer
The total number of acidic amino acids found in human proteins is **2**.

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