This feature of DNA is termed complimentary base pairing, in that the base that compliments a certain base, say A, is always paired with base T, and likewise every T has its pair partner always as A. The same holds true with C with G, and vice versa.
Microorganims are widespread in nature and are beneficial to life, but some can cause serious harm. They can be divided into six major types: bacteria, archaea, fungi, protozoa, algae, and viruses.
