The sac that surrounds and protects the heart is called the:

Of seawater increases with decrease in the temperature. therefore, the cold water sinks to the deeper layers at the bottom

Fill in the blank with the best word to complete the sentence. white blood cells protect against and aid in blood clotting when injuries are sustained.

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.