1 the set of exogenic (physical, chemical and biological) processes that alter the physical and chemical state of rocks at or near the earth's surface.  intensity of most weathering decreases with depth, because variations in temperature and moistures decrease with depth.
A gene is a segment of nucleic acid that contains the information necessary to produce a functional product, usually a protein. Genes consist of a long strand of DNA (RNA in some viruses) that contains a promoter, which controls the activity of a gene, and a coding sequence, which determines what the gene produces.
The functional segments of DNA which code for the transfer of genetic information are called genes. With four possible bases, the three nucleotides can give 4 3 = 64 different possibilities, and these combinations are used to specify the 20 different amino acids used by living organisms.he ribonucleic acid (RNA) that is directly involved in the transcription of the pattern of bases from the DNA to provide a blueprint for the construction of proteins is called messenger RNA or typically mRNA.