Question

Q50. The bonemarrow is absent in:
में अनुपस्थित होती है:-
(a)Reptillia/ सरीसृप
(c)Fishes/ मत्स्य
(b)Amphibia/ उभयचर
(d)Birds/ पक्षियों में​

Answer 1

Explanation:

Bone marrow is absent in aves. Their endoskeleton is fully ossified (bony) and the long bones are hollow with air cavities. Such bones are known as pneumatic bones. It is an adaptation for aerial life of birds.

answer is aves