What do all organisms have ?

14. which of the following codons code for threonine? a. ucg b. ugu c. cga d. aca

Which of the following determines the specificity of a dna probe? a. type of radiation b. level of enzymatic activity c. number of neutrons d. complementary base pairing

What is point source pollution of an aquatic ecosystem? a) pollution of freshwater sources b) pollution from many sources that combine into one c) pollution that occurs over a wide area; water that runs off from fields, parking lots, and other land surfaces d) pollution that can easily be identified with a single discharge source, such as an open pipe which drains into a body of water