Use the image below to answer the following question

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

Turtle hatchling survivorship rate is low in many turtle species due to predation. amanda researched the predatory rate on a species of turtle eggs in the red river. the eggs were harvested from trapped turtles and the egg's cloaca film (reproductive discharge) was either washed off or left on once gathered. research suggests that predators use the female's cloaca scent to locate the eggs. the eggs were only handled when wearing gloves and then reburied along islands where the turtles were trapped. the nests were monitored by cameras and manually on foot and data on nest predation were recorded. a. based on the experimental design, what is the dependent variable? b. based on the experimental design, what is the independent variable? c. based on the experimental design, what is the control?

What initially causes a nerve impulse? release of enzymes out of the neuron movement of chemicals into the dendrites of the neuron pathogens attacking the dendrites of the neuron red blood cells bathing the neuron