Compare And Contrast Directional Selection And Disruptive Selection

Decent Essays
Jessica Northey
Exam Number 250104
1.Compare and contrast directional selection and disruptive selection, Provide and example of each.

Directional selection and disruptive selection differ because instead of the subject only going in one direction it will split off and go two different ways for example if some flowers and their colors. The main colors may be red, pink and white primarily, and the more dominate color being a pink flower. But if we remove the pink flower completely from the equation then the flowers will shift toward the dominant white color over the red. In a directional selection there is only one trait and it is always that dominant trait that dictates body of the population. The best example to show this is that in the
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Many pathogenic bacteria species are becoming resistant to antibiotic. Explain how such adaptations can develop through the process of natural selection.
Bacteria are not just all of a sudden becoming resistant to antibiotics they have always had a bit of resilence, as a human species we have always developed something it doesn’t work we will develop something stronger, that has been the downfall in this instance. Pencillan is a great example as it is one of the most highly used antibiotic and is derived and made from mold. Scientist knew that certain mold could kill bacteria but some of those bacteria would also compete with the anitbiotics for nutrition from the mold. So in other words there has been a form of antibiotic resistant from the beginning.

When non-resistant bacteria are exposed to an antibiotic, most of them die. But due to the increase of mutations some of the bacteria are becoming resistance to the antibiotic. The bacteria are all subject to natural selection. Natural selection is as simple as saying that the bacteria that have not developed a mutation or resistance that helps them to survive die. The ones that do, survive and pass on the mutation to the next generation. This means that we are constantly having to adapt our antibiotics because so much of the mutation is getting passed along. The flu vaccination is a good example of how mutations are carried over and how the vaccine had to be changed every year to fight the ever changing virus. Some strains
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Vertebrates are known to be animals with backbones. Tooth reduction is one of the major evolutionary trends that developed among major vertebrate groups that allowed for the transition from aquatic to terrestrial life. Evolution of limbs and being able to breath air are other evolutionary trends that took placeThese trends include improved respiration and protective and insulating body coverings. More over the transition from water to land also included changing to more efficient reproductive methods like having a placenta for some animals or egg layers for other animals. Lastly, the morphology of organisms evolved such that for land they would have paired, muscular appendages used for crawling and
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