Question

How is a bird’s body adapted to flying?

Answer 1

Hint: In birds, it was seen that their forelimbs are modified to a specific structure which has many important functions in making the life of birds easy and increasing their chances of survival.

Complete answer:
Forelimbs of birds are modified into the special structure known as the wings that help them to fly. These wings create a downward force that helps the birds to lift up.
The bodies of birds are adapted for flying. Many of a bird's bones are less dense than the bones of humans which makes birds' bodies lightweight. Flying birds have large chest muscles which help to move the wings. Birds have feathers that help them fly. The long flight feathers on the wings and tail help birds to make the balance while flying. In addition, birds have a system of air sacs in their body that hook up with the lungs. The air sacs enable birds to extract far more oxygen from each breath of air than other animals can. Extra oxygen is required by the birds to release large amounts of energy to power their flight. Birds get more oxygen because of their four-chambered heart. The advantage of a four-chambered heart is that there's no mixing of oxygen-rich and oxygen-poor blood. Blood that arrives within the bird's body tissues has much oxygen.

Note: Birds even have well-developed brains and keen eyesight. During flying, birds must have very quick reactions. When landing on a tree or cliff, a bird has only a few seconds to identify an area to land safely and avoid crashing. Most birds have keener eyesight than humans do.