How many essential amino acids are there in following list ?
(a) Glycine
(b) Proline
(c )Alanine
(d) Lysine
(e ) Tryptophan
(f ) Cysteine
(g) Valine
(h) Arginine
(i) Leucine
(j) Histidine

Answer

To determine how many essential amino acids are present in the given list, we will first identify which amino acids are essential and which are non-essential. Essential amino acids are those that cannot be synthesized by the body and must be obtained from the diet.

### Step-by-Step Solution:

1. **List the Amino Acids**:
- Glycine
- Proline
- Alanine
- Lysine
- Tryptophan
- Cysteine
- Valine
- Arginine
- Leucine
- Histidine

2. **Identify Essential Amino Acids**:
- Essential amino acids are typically defined as those that the body cannot produce on its own. The essential amino acids for humans are:
- Lysine
- Tryptophan
- Valine
- Arginine
- Leucine
- Histidine

3. **Check Each Amino Acid from the List**:
- **Glycine**: Non-essential
- **Proline**: Non-essential
- **Alanine**: Non-essential
- **Lysine**: Essential
- **Tryptophan**: Essential
- **Cysteine**: Non-essential
- **Valine**: Essential
- **Arginine**: Essential (conditionally essential)
- **Leucine**: Essential
- **Histidine**: Essential

4. **Count the Essential Amino Acids**:
- From the list, the essential amino acids identified are:
- Lysine
- Tryptophan
- Valine
- Arginine
- Leucine
- Histidine
- Total count of essential amino acids = 6

### Final Answer:
There are **6 essential amino acids** in the given list.