<span>There needs to be an independent variable, a dependent variable, a constant, and a control group. The independent variable is the part that is manipulated. The dependent variable is affected by the independent variable. The constant is the part kept the same throughout all of the experiments. The control group is the normal group that is untreated.</span>
<span>The correct option is A. Dark age are so called because compare to other eras, historian don't know much about this era. This period of time is considered lost to history, no important record about the era has survived, The cause of the dark ages was the collapse of the Roman Empire and the invasions and raiding that characterized it.</span><span />
In the two maps that show the allele frequency of sickled hemoglobin (HbS) and malaria endemicity in Africa, it can be seen that in the regions with no malarial outbreak or malaria-free areas coincide with the grey to lighter shades of red in the heat map of the allele frequency of HbS. The color coding in the heat map for the allele frequency tells us that the frequencies range from 0 to 2.02 in the malaria-free areas.
Hence the answer is A)When an area is malaria free, the HbS allele frequency is between 0 and 2.02.
Answer:
Cell deterioration
Explanation:
Once the cells first come in contact, they immediately create a cell shield that is composed of weaker cells, while the rest continue their work, the problem with this, is that their is a lack of cells to do work and the weaker cells are slowly dying and creating holes for the harmful chemicals to enter, as the cells deteriorate they clot together and create a lump in a final attempt, and it ends up creating deadly weight in the lungs.
