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.
1 A gene is a small section of DNA that contains the instructions for a specific molecule, usually a protein. 2  The purpose of genes is to store information. 3  Each gene contains the information required to build specific proteins needed in an organism. In humans, alleles of particular genes come in pairs, one on each chromosome (we have 23 pairs of chromosomes). 2  If the alleles of a particular gene are the same, the organism is described as homozygous for that gene. 3  If they are different the organism is described as heterozygous for that gene.