All life on earth started as unicelluar, prokaryotic organisms. which of these structures was vital for organisms to develop in order to evolve into more complex, multicellular organisms?
a) nucleus
b) ribosomes
c) cytoplasm
d) cell membrane

primary succession occurs in essentially lifeless areas regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. secondary succession occurs