Which choice has allowed scientists to learn about the internal structure of the mitochondrion? 1
studies of the chemical activity of enzymes
2.
the development of wet-mount techniques
3.
electron microscope studies
detailed studies of chromosomes

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.

Explain how fossils scientists make discoveries about the lives of organisms and about how environments have changed over time. plz hurry up it time

What is the term for a water wave that is created by an underwater earthquake?