Question

Which character is not the same in aves and mammals?

• A. Single systemic arch
• B. Metanephric kidney
• C. Seven cervical vertebrae
• D. Homoiotherms

Answer 1

The correct option is C Seven cervical vertebrae

Only mammals have seven cervical vertebrae. Both mammals and birds are homeotherms i.e maintain a constant body temperature due to their internal body metabolism. Kidney is metanephric in reptiles, birds and mammals. In birds and mammals there is single systemic arch. In birds only the right arch is present in adults and in mammals only the left arch is present in adults. Thus, the correct answer is option C.