SCI115 SUsci115 week 5 discussion AND response

Week 5 DiscussionCOLLAPSE”Apoptosis, Crossover, and Tumor-suppressor genes”This week?s discussion is focused mechanisms that cells use to keep cell division under control, to prevent cancer, and to function well. For your primary post, respond to one of the following three topics. Also, please reply to at least one fellow student on any topic.Topic 1 : Apoptosis. Watch the Khan Academy video about apoptosis (1)*, then answer the following questions in your own words:Topic 2 [article]: Crossover. Read the article from the University of Rochester on a gene that influences crossover rates in fruit flies. Then address the following: Topic 3 [research]: Tumor-suppressor genes versus Proto-oncogenes. This is a library-research topic in which you are required to provide your sources. Mutations in tumor suppressor genes can contribute to or cause cancer, just as mutations in proto-oncogenes can also contribute to or cause cancer. However, tumor suppressor genes are very different from proto-oncogenes.References:AND RESPOND TO THIS POST:Sylve RE: Week 5 DiscussionCOLLAPSEGood evening Classmate and ProfessorTopic 2: Crossover(a) Explain the relationship between crossover, genetic diversity, and natural selection.The exchange of genetic material by crossing over is important to natural selection. Therates of genetic crossovers have evolved to strike a balance between the benefits of crossing overand the risks of selfish DNAs. When there is a wide range of genotypes to work on, naturalselection will work excellently. Mixing up different combinations of alleles by crossover orrecombination brings about the diversity which controls the process of natural selection (Valich,2018).(b) Summarize the findings regarding a gene that influences crossover.The gene that influences crossover in fruit flies is the MEI-208 gene. This gene controlsthe recombination rate. The gene controls the differences in the rate of crossing over betweenspecies and the evolutionary forces involved. It is the first known gene, which scientists haveshown to be accountable for the evolution of the rates of recombination. The two fruit fliesspecies that were researched were the Drosophila melanogaster and the Drosophila mauritiana.The sequences of the DNA in the two species were very different. The D. mauritiana specieshas more crossing over to about 1.5 times of the D. melanogaster species (Valich, 2018).