1
animals that develop and are born within an eggson classified
2
animal whose embryo develops, after fertilization, in a specialized structure within the womb of the female
3
thick skin protected by a protective cornea layer of scales
4
vertebrate animals that have mammary glands that produce milk to feed their young.
6
aquatic vertebrates that breathe through gills
7
bones firm, hard and resistant organ gills respiratory organs of numerous aquatic animals
8
bones firm, hard and resistant organ
9
Extremities transformed into organs for flight
10
organs in which the blood receives oxygen from the air and in turn the blood is released from the carbon dioxide which passes into the air.
11
group of vertebrates specialized in flight
12
larger organ
