Some bird bones are hollow rather than honeycombed. The hollow bones mostly contain air sacs. The replacement of bone marrow with air sacs is properly understood as an adaptation to
A) reduce the weight of the bird.
B) facilitate flight.
C) eliminate the functions that marrow performs.
D) All three of the options listed are correct.
E) Only two of the options listed are correct.

Question

Quizplus · Accepted Answer

The hollow bones in birds, containing air sacs instead of bone marrow, serve primarily to reduce the weight of the bird (A) and facilitate flight (B). These adaptations are crucial for flight efficiency and maneuverability. The statement about eliminating the functions that marrow performs (C) is not accurate as the primary purpose of this adaptation is not to eliminate marrow functions but to optimize for flight.

Some Bird Bones Are Hollow Rather Than Honeycombed