Literary Physics

Syllabus dot capitulum Notes * process information from secondary sources to describe an example of hybridisation inwardly a species and explicate the purpose of this hybridisation Hybridisation deuce genetically different strains of an organism argon crossed to produce offspring with plummy characteristics. i. e. cross breeding cattle to produce better meat, which will public assistance for human consumption Selective breeding of sheep to produce merino sheep which are hybrids produced by interbreeding other sheep varieties.Interbreeding other varieties of corn to produce the resolution hybrid corn that was hardy and produced large fruit. * describe the process of deoxyribonucleic acid replication and explain its signifi empennagece * desoxyribonucleic acid double helix unwinds * DNA unzips * Nucleotides are added to each(prenominal) single strandDNA replication ensures that the genetic information is maintained. * explain the relationship between proteins and polypeptide s A protein is made up of wiz or more polypeptides.A polypeptide is made up of a chain of many another(prenominal) aminic acids. * analyse information from secondary sources to outline the evidence that led to Beadle and Tatums one gene one protein hypothesis and to explain why this was modify to the one gene one polypeptide hypothesis Beadle and Tatum concluded that for each defective enzyme there was one gene on one specific ambit of a chromosome that had been mutated by irradiation. This led to their one gene-one enzyme theory.The one gene one enzyme hypothesis changed to the one gene one protein hypothesis, once it was demonstrated that there are other proteins besides enzymes that are en recruitd by genes. Thomas Morgans browse led to a greater understanding of how genes are arranged on chromosomes and how genetic material can be exchanged (during crossing over) in meiosis. Morgans experiments showed without any doubt that * the gene for midriff colour in fruit fl ies is located on the X chromosome, and * hereditary factors can be exchanged between the X chromosomes of an individual.Morgan experimented with fruit flies (Drosophilia melanogaster) and resolved that genes are carried on chromosomes. He used crossing over to discover locations of genes. He discovered that sex chromosomes look different to each other, and that eye colour gene in Drosophilia was located on the X chromosome, jumper cable to the discovery of sex linkage. Boveri experimented with sea urchins and showed that a complete set of chromosomes was necessary for normal development and that the NUCLEUS of a cell was concerned with inheritance.He postulated that each chromosome was different, chromosomes were transferred from one generation to the next during cell division, and that chromosomes must carry the many hereditary factors. Sutton he observed during meiosis that chromosomes behaved randomly and gametes receive exclusively one chromosome from each pair. Distingu ish between the terms gene and allelomorph A gene is a section of DNA that codes for proteins that expresses itself as the phenotype for example, two genes for eye colour. An allele is the alternative forms of a gene, i. e. for eye colour, B would code for blue while b for brown.