How are reptiles and mammals alike?

Answer 1

1. Both breathe oxygen.

2. Both have internal fertilization.

3. Neither have larval stages.

4. Both are amniotes.

5. Both have bilateral symmetry.

6. Both have spines and backbones.

7. There are many internal organs common to both reptiles and mammals.

8. Both are tetrapods by descent, although snakes no longer have limbs.

Answer 2

1. Both breathe oxygen.

2. Both have internal fertilization.

3. Neither have larval stages.

4. Both are amniotes.

5. Both have bilateral symmetry.

6. Both have spines and backbones.

7. There are many internal organs common to both reptiles and mammals.

8. Both are tetrapods by descent, although snakes no longer have limbs.

Answer 3

• Reptiles and mammals both have a backbone and a notochord, so they are vertebrates.
• They both have a full respiratory system, converting oxygen into carbon dioxide.
• They both have brains, hearts, lungs and livers.

The differences are that mammals are warm-blooded, or endothermic, meaning that they regulate their own body temperature. Reptiles are cold-blooded, or ectothermic, meaning they cannot regulate their own temperature, so their body temperature changes with their environment.

How these animals reproduce is also very different. The majority of mammals give live birth, with only two exceptions - the two monotremes, which are tye platypus and the echidna. All mammals feed their young on mothers' milk, regardless of the species. While most reptiles lay eggs, there are a significant number that give live birth. In contrast to mammals, most reptiles do not look after their young, because reptile young are hatched or born fully developed, they are able to fend for themselves almost immediately. Generally, mammals' offspring take longer to grow and mature than reptiles.

Answer 4

Bones, two eyes, tongue, five fingers, backbone, lungs,