Ais a natural location where warm or hot water flows up from underground.
a. fault
b. fissure
c. volcano
d. hot spring

DNA is composed of building blocks called nucleotides. In the structure of DNA, nucleotides are composed of codons which are made up of nitrogen bases: adenine, guanine, uracil and thymine. In this case, adenine and guanine are paired while uracil and thymine are on the other hand paired. The different combinations pertain to different DNA make-up