Describe human alimentary canal . Draw a labelled diagram of human alimentary canal.

Explanation

### Step-by-Step Solution:

1. **Introduction to the Human Alimentary Canal**:
The human alimentary canal is a long, continuous tube that starts from the mouth and ends at the anus. It is responsible for the digestion and absorption of food.

2. **Mouth**:
The process of digestion begins in the mouth, where food is ingested. The mouth contains the buccal cavity, which secretes saliva. Saliva contains the enzyme salivary amylase that begins the digestion of starch.

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