Physical life science concepts and applications

Physical Life Science

Genes are the basic genetic material or the fundamental 'building blocks' of life. They are made up of spiraled sequences called DNA. (Deoxyribonucleic acid). They provide instructions for the cells and are responsible for specific traits of the body. Proteins are vital amino acids synthesized within the body that control the structural (hair, nails, etc.) and functional aspects (enzyme functions, saliva, digestive enzymes, muscle movement (myosin), etc.) of the entire cellular network of the body. Genes are like the 'blueprint for protein synthesis' and every gene is responsible for coding for a particular protein or a segment of a polypeptide. Genes and proteins are associated in a complex relationship, while the genes encode for proteins the proteins in turn control the expression of a gene.

Since the completion of the human genome project in 2003 the issue of genetic screening for hereditary diseases has become a much-debated one with ethical undertones. Presently researchers have found more than 4000 genetically inherited diseases and results have identified the specific genes responsible for more than 450 of them. [Cherie Dimaline]. For parents who have a family history of chronic genetically inherited degenerative diseases genetic screening would offer a scientific way to know the predisposition of their children to such diseases. Particularly for chronic disorders such as cystic fibrosis, Tay-Sachs disease, muscular dystrophy and sickle cell anemia genetic screening and counseling will provide prospective parents with enough information about the potential risk and would also give them more time to make informed decisions regarding future pregnancies. Further, the genetic counselor can also discuss treatment options if they are available for a particular genetic condition. Gene therapy is already being tested for Muscular Dystrophy and as molecular medicine advances more genetic disorders can be successfully managed. [Dr. Joseph F. Smith]

3) the DNA (has a double helical structure) is the principal component of the chromosomes while the gene is actually a segment of the DNA molecule, which can code for a particular protein. Genes control the production of proteins, which control the structural and functional metabolism of the body. [IBAC] Transcription is nothing but copying of the gene sequence from the DNA to the mRNA. During the gene decoding process the double stranded DNA splits up to reveal a single strand from which the base sequence of the gene is copied onto a single stranded nucleic acid known as the messenger ribonucleic acid or mRNA. This implies that we have an exact copy of the gene base in the mRNA except that Urasil (U) replaces the T. base and deoxyribose is replaced by ribose. Translation on the other hand is the actual process of protein synthesis from the mRNA strands. Ribosomes work with the mRNA for protein synthesis within the cells. [the State University of New York]