Originally posted by cindtan29:
ah gene...rem the meaning of ur nick??? .....
how can i miss u out from the top class.....
Gene = Genes are entities that parents pass to offspring during reproduction. These entities encode information essential for the construction and regulation of polypeptides, proteins and other molecules that determine the growth and functioning of the organism.
The word "gene" is shared by many disciplines, including classical genetics, molecular genetics, evolutionary biology and population genetics. Because each discipline models the biology of life differently, the usage of the word gene varies between disciplines. It may refer to either material or conceptual entities.
Following the discovery that DNA is the genetic material, and with the growth of biotechnology and the project to sequence the human genome, the common usage of the word "gene" has increasingly reflected its meaning in molecular biology. In the molecular-biological sense, genes are the segments of DNA which cells transcribe into RNA and translate, at least in part, into proteins.
In common speech, "gene" is often used to refer to the hereditary cause of a trait, disease or condition—as in "the gene for obesity." Speaking more precisely, a biologist might refer to an allele or a mutation that has been implicated in or is associated with obesity. This is because biologists know that many factors other than genes decide whether a person is obese or not: prenatal environment, upbringing, culture and the availability of food, for example.
Moreover, it is very unlikely that variations within a single gene—or single genetic locus—fully determine one's genetic predisposition for obesity. These aspects of inheritance—the interplay between genes and environment, the influence of many genes—appear to be the norm with regard to many and perhaps most ("complex" or "multifactoral") traits. The term phenotype refers to the characteristics that result from this interplay (see genotype-phenotype distinction).