How do mammals compare with birds and reptiles in terms of temperature regulation and structure of the heart?

Photosynthesis converts light energy to chemical energy. which molecules are the end product of this transformation of energy in this reaction?

Animal bodies (and even plant bodies for that matter) are complex enough that life couldn't exist without enzymes. enzymes are usually large, complex biological catalysts that are expensive to make. enzymes speed up the rate of chemical reactions without being used up during the reaction (they can be reused many times). they are highly specific in the reactions they regulate. knowing what enzymes are and how they function, why does this explain why complex life forms could not exist if there were no enzymes.

What type of weather does tropical continental air bring in summer? hot and cloudy cool and sunny hot and sunny cool and cloudy