Answer:
A
Explanation:
A, the guy with 1 star provided the most noneducational response I've ever seen.
Answer:
The ozone layer in the stratosphere blocks out the sun's deadly ultraviolet rays. It acts as our planet's natural sunblock.
Answer(s):
Thick Fur on a bear: Physiological
Spines on a rose bush: Structural
Hibernating for the winter: Behavioral
Fight or Flight reflex: Behavioral
Deer fighting for a mate: Behavioral
I hope these help and I am sorry if these are wrong. ;-;
Answer:
Humans have a heart with two atria and two ventricles that pushes blood in one direction. Some animals have hearts similar to humans but, other animals have only one atrium and one ventricle or a cardiovascular system that can push blood in two directions.