How do birds digest their food in the absence of teeth?

They have a gizzard to grind the food.

Explanation:

Birds cannot chew since they have no teeth. However, the beak allows them to split very large seeds or swallow them directly.

For their digestion they have a stomach where digestion enzymes are released. Also they have a gizzard that is an organ that grinds the food mechanically. This gizzard usually has small stones inside that were previously ingested and that helps to digest the food.

really dont know just need some points

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