Allele frequency

for the HbS allele and thus inevitably develop sickle cell anemia.…

Introduction Charles Darwin is famous for his book, The Origin of Species, where he proposed that evolutionary change in populations is due to natural selection. His idea was that of survival of the fittest. In other words, the species with superior traits would have more of a likelihood to live, and then breed more offspring. Slowly, more and more of the species with the superior traits will survive and multiply. But what is it that gives these species the better survival trait, and allows…

These show that there is selection against the shorter wavelength (535 nm) alleles in favour of 560 nm alleles or intermediate wavelength pigments (e.g. 545 nm; Osorio et al., 2004). Assuming that trichromacy favours the 535 nm/560 nm combination with equal allele frequencies, it is likely that the bias against the 535 nm allele arises in dichromats. This could be due either to the consequences for their dichromatic colour vision, which favours a wide…

For this lab we conducted a population genetics study on the frequency of wild and apterous flies within a small population of fruit flies. The fruit fly Drosophila works well for genetic and evolutionary geared studies because they have a relatively short generation time but are intricate enough to reveal some biological principles that are parallel to many different kinds of eukaryotic organisms. When exposed to artificial selection in laboratory experiments, fruit flies have experienced…

From a genetic point of view, it is the change in frequency of an allele or genotype, within a population, regardless of mutations, natural selection and migration. Genetic drift is caused by random and unpredictable phenomena, like, the chance that sperm and eggs may encounter, in the case of sexual reproduction. The effects of genetic drift are all the more important as the population is small, because the deviations from the allele frequencies there will be more noticeable. This situation can…

Genetic drift is a mechanism of evolution that occurs by random chance rather than natural selection. In genetic drift, a population experiences a change in the frequency of a given allele, prompted by random luck rather than a need for adaptation. This differs from natural selection, in which allelic frequency is altered based on the fittest genes surviving to reproduce and the weaker genes dying off. Genetic drift tends to be a phenomenon amongst smaller populations, while natural selection…

Microevolution allows us to see a small scale of evolution over a short period of time. To visually see and test evolution we need organisms that adapt quickly and have short life spans. Fruit flies, Drosophila melanogaster, are model organisms in order to gather as much information within a short period of time. Fruit flies have a life span of about 2 weeks, and are low maintenance, making it easy to see several generations. (Varga, S. J., Qi, C., Podolsky, E., & Lee, D , 2014) According to…

of the polymorphism is dependent on the drug and the variant alleles expressed because individual allele variants can lead to a range of metabolic ability from ultrarapid metabolizers (UMs) to poor metabolizers (PMs). There have been 74 identified allelic variants of the CYP2D6 gene and the number seems to be increasing. Within the population there are fully functional alleles, alleles with reduced function, and non-functional alleles (null). The genotype of the individual indicates the level of…

The interaction of these forces with other environmental aspects is very critical to manipulating the genetic models within organisms and their frequencies. In the past, this is interaction and action of these forces in generations have led to the formation of the changes that are experienced in the world today through the existence of different species that may have originated from the same ancestor…

. The four forces of evolution are mutations, natural selection, genetic drift, and gene flow. Mutations are changes in genes that make us who we are today. Mutations, although they are changes in our genetic code, are most of the time harmless and essential to evolution. Mutations can be either advantageous, deleterious, or neutral depending on what the environment of the living organism is (class lecture, Wednesday). The next force of evolution is natural selection which is the idea that…