Question

Define the structure of bird​

Answer 1

Birds have light-weight bones that are filled with air. They also lack a jaw, which in many vertebrates is a dense, heavy bone with many teeth. Instead, birds have a light-weight keratin beak without teeth. Birds have air sacs that store inhaled air and push it into the lungs like bellows.

Answer 2

Explanation:

Birds have light-weight bones that are filled with air. They also lack a jaw, which in many vertebrates is a dense, heavy bone with many teeth. Instead, birds have a light-weight keratin beak without teeth. Birds have air sacs that store inhaled air and push it into the lungs like bellows.

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