Question

Scale, feather and hair form _______ of vertebrates​

Answer 1

Explanation:

Vertebrate animals have developed some very interesting excrescences, or projections of the skin, some of which are well-known and easily oberved by most people. They are scales, feathers, and hair.

Answer 2

Explanation:

Vertebrate animals have developed some very interesting excrescences, or projections of the skin, some of which are well-known and easily oberved by most people. They are scales, feathers, and hair.