Asked by Anonymous

The single defining characteristic of the mammals is the presence of?
mammary glands.

a placenta.

hair.

warm blood.

a skul
Answered by Ms. Sue
Look up the meaning of mammal.
Answered by Anonymous
its placenta..
Answered by Ms. Sue
No.

http://www.merriam-webster.com/dictionary/mammal
Answered by Anonymous
Hair is part of it so hair