Biology True or False??

Question

1) All vertebrates have internal skeletons.
2) All vertebrates have skeletons made of bone.
3) Birds have oxygenated air in their lungs at all times.
4) Hair in mammals has no use other than warmth.
5) In mammals, glands secrete both sweat and milk.
6) There are more species of perching birds than there are species of all placental mammals.
7) A monotreme is a mammal that reproduces by laying eggs.
8) Some behavior patterns can be inherited.
9) A creature will exhibit aggressive behavior only against animals of a different species.

I think 9 is false males do it against other males right?

Answer 1

1) True
2) False
3) False
4) False
5) True
6) True
7) True
8) True
9) your right it's False

Answer 2

1 F 2 T 3 T 4 T 5 F

Answer 3

I agree that 9 is false.

4 is also false. Mammals stand hair on end to make themselves look bigger to a predator. Porcupines and hedgehogs have hair modified into spines. Hair holds scent on the body.

I don't know about the birds in 3 and 6.