Differentiete between heat and temperature in molecular level.

Yes it's easy. it makes easy to follow because while you are reading you can understand what are you reading for and it's difficult because even you are reading you didn't understand what your reading for it might be you don't know the meaning of each words

It's called sexual reproduction. there are 2 types of it. internal and external.. internal happens when male animal realeases sperm to the female animal's body.mostly cats,dogs,birds,cats,insect,ect undergo internal.
external
the baby fertilizes on the egg. in animals like chickens, the hen gives heat to the egg to fertilizes the egg. for fishes and frogs, the female realeases eggs into the water or attaches them to a plant or rock.the male realeases sperm cells over the egg to fertilize them.

The "circulatory" system is well-named because the "blood" goes in a circle that starts in the pumping "heart", moves through the whole "circulatory system" and comes to the "heart" again.

not sure with my answer but i hope it helps : > study well

Did you know what the answer is? can you tell me? thank you =)