Answer:
(c) directional selection
Explanation:
Directional selection is a type of natural selection that occurs when members of a population of a species with a particular extreme phenotype is selected or favored against the other phenotypes when natural forces act on the population of a species. Individuals having the particular traits that are favored survive and become more common that others with traits that are less favored.
Directional selection may likely result in the species of butterflies in which darkly collared butterflies are not preyed upon, ensuring their survival, while the other butterflies with other colors will be phased out with time. Darkly colored butterfly will be selected for while the others will be selected against.
<span>Hippocrates believed that there are four humors in human body which need balance for a healthy being. These were:
Blood, phlegm, yellow bile, and black bile.</span>
Galen expanded the idea of the humors and introduced four temperaments which were these:
choleric (hot / dry), melancholic (cold / dry), sanguine (warm / moist), and phlegmatic (cold / moist).
Another expansion Galen did was that he gave each humor/temperament physical and psychological qualities and said that even the food items have an association with the certain humor, those foods can effect certain humor in certain ways.
Once you finish
growing to adulthood, neurons stop dividing. Hair follicle cells constantly
divide throughout your lifetime since they are constantly producing cells that
become part of the hair itself as they die. So in an adult, the rate of cell
division for neurons is zero (although there is some counter-evidence but it is
certainly very low) while the hair follicle rate is much higher on the order of
once every few days or faster.
Answer/Explanation:
(1) a mutation in the coding region, resulting in an inactive protein
To check to see if there is a mutation, you could extract the DNA from the cancer cells and then perform PCR to amplify the gene of interest. You could then perform sanger sequencing and compare the sequence to the normal gene to see if a mutation is present. To test the effect of the mutation, you would want to see if an active protein has been formed.
To see if a normal sized protein has been formed, you could perform a western blot, comparing the protein band to the WT protein band. If the protein is absent or much smaller, it is likely not a functional protein.
(2) epigenetic silencing at the promoter of the gene, resulting in reduced transcription.
To check for changes in the epigenetic landscape of the promoter, you could perform chromatin immunoprecipitation by extracting the chromatin from the tumour cells and using antibodies for different chromatin marks to see what has changed between the normal cells and the tumor cells. E.g. H3K9me3, H3K27me3. You would perform a pull down with the antibody of interest and then PCR for your promoter to specifically look at changes at that gene compared to normal cells. To test DNA methylation, you could perform bisulfite sequencing.
To see how transcription is affected, you could extract RNA from the tumor and normal cells, and compare the levels of RNA between the two samples by qRT-PCR
The correct answer is option D, South Africa
Prince Edward Islands is found in the South Africa in the sub Antarctic Indian Ocean.
