Will give brainliestwhich of these statements is correct about how the first forms of life appeared on earth? non-living molecules evolved into living molecules by chemical changes. reproducing molecules evolved into living organisms by biological processes. rocks and fossils were transformed into living molecules by biological processes. atmospheric gases were transformed into living organisms by chemical changes.

The answer is B: Reproducing molecules evolved into living organisms by biological processes.

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.