Question

Flight muscles of bird are attached to
A) Clavicle
B) Coracoid
C) Keel of sternum
D) Scapula

Answer 1

Flight muscles are found in all birds and these muscles are used to control the wing during flight. The wings are raised by a contraction of muscles attached to the base of the wing inside.

Complete answer:
Option A) Clavicle – is an incorrect answer because clavicle or collarbone is a long bone that serves as a strut between the shoulder blade and the sternum (breastbone). There are two clavicles, one on the left and one on the right. The clavicle is the only long bone in the body that lies horizontally. Thus, this is an incorrect answer.
Option B) Coracoid – is an incorrect answer because the coracoid process is a small hook like structure on the lateral edge of the superior anterior portion of the scapula. Thus, this does not help birds to fly. Thus, this is an incorrect answer.
Option C) Keel of sternum – is the correct answer because flying birds have a keel - a ridge on the sternum or breastbone, which is a main site of attachment for flight muscle. Thus, this is the correct answer.
Option D) Scapula – is an incorrect answer because this is also known as the shoulder bone, shoulder blade, wing blade or blade bone, is the best that connects the upper arm bone with the clavicle (collar bone). Thus, this is an incorrect answer.
Hence the correct answer is option ‘C’.
Note: The keel of the sternum is the breast bone where flight muscles are attached to the body. It increases the surface area for muscle attachment. The pectoralis (thick, fan shaped muscle, situated at the chest of the human body) major, the lower muscle on the keel inserts in the humerus and it contracts, pulling the wing down.