Ascientists wishes to determine whether or not a marine ecosystem underwent primary or secondary succession in the past. what evidence would be most useful for making this determination?
unearth the fossil history of the ecosystem to find producers that can live on rock.
use radiocarbon dating to determine the age of the rock underlying the ecosystem.
determine the average age of all producer species in the ecosystem at the present time.
determine the chemical composition of the water in the ecosystem at the present time.

both anaerobic and aerobic respiration use glucose (or other carbohydrates), proteins and lipids to produce atp and nadh. cell uses those energy molecules, obtained from food and   breaks them down during the chemical reactions of respiration. in anaerobic respiration, nadh is regenerated to nad+ by enzymes lactate dehydrogenase (lactate is produced, e.g. in muscle cells) or by alcohol dehydrogenase where ethanol is produced (alcohol fermentation), while in aerobic respiration, electrons from nadh are deposited in the mitochondria to regenerate nad+ (electron transport chain. anaerobic respiration produces 2 atp per molecule of glucose compared to aerobic respiration where about 38 atp molecules are produced.