All energy is an ecosystem starts as

Which beat describes the brain stem

Body temperature is tightly regulated in mammals for example when external temperatures drop too much the body of a mammal responds by in order to its core temperature?

The genetic code is essentially the same for all organisms. based on this information, one can logically assume which of the following statements to be correct? a. dna was the first genetic material. b. the same codons in different organisms translate into the different amino acids. c. different organisms have different numbers of different types of amino acids. d. a gene from an organism can theoretically be expressed by any other organism. e. all organisms have experienced convergent evolution.