Cells, tissue, organs, organ systems
for one and c are closer alike to each other as the rates of recombination depend on the likeness of that gene
Convection occurs over a very very long time in the earth's mantle. Rock slowly gets melted down from the core, then shoots back up from volcanoes. The new rocks get buried by sand and sediments, and the process resets.
He showed that flies did not grow from meat that was not exposed to air
