Mainly food digestion in earthworm occurs in

Options

A. Gizzard
B. Mouth
C. Buccal cavity
D. Stomach

Answer

### Step-by-Step Solution:

1. **Understanding the Digestive System of Earthworm**: The earthworm has a complex digestive system that includes several parts: mouth, buccal cavity, pharynx, esophagus, gizzard, stomach, and intestine.

2. **Ingestion of Food**: The process of digestion begins when food enters through the mouth, which is the first cavity. The mouth leads to the buccal cavity.

3. **Role of the Buccal Cavity**: The buccal cavity is muscular and helps in holding the food during ingestion. It then leads to the pharynx and subsequently to the esophagus.

4. **Function of the Esophagus**: The esophagus serves as a passageway for food to move from the pharynx to the gizzard. It plays a role in the digestive process but is not the main site for digestion.

5. **Importance of the Gizzard**: The gizzard is a crucial organ in the digestion of food in earthworms. It is oval-shaped, muscular, and is located between the 8th and 9th segments of the earthworm's body. The gizzard is responsible for the churning and grinding of food, making it a significant site for mechanical digestion.

6. **Stomach and Intestine**: After the gizzard, food moves into the stomach, which is a narrow, thin-walled structure extending from the 9th to the 14th segment. The stomach contains calciferous glands, and while some digestion occurs here, the main digestive activities take place in the intestine, which is a long, tubular structure extending to the last segment.

7. **Conclusion**: Based on the information provided, the main site of food digestion in earthworms is the gizzard due to its role in mechanical processing of food.

### Final Answer:
**Mainly food digestion in earthworm occurs in the gizzard.**

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