Atrazine is an herbicide that prevents plant growth by inhibiting photosynthesis. atrazine works by binding to proteins in the electron transport chain of photosystem ii. once atrazine binds to the proteins, electrons can no longer travel down the chain to reach photosystem i. based on this information, how does atrazine stop plant growth?

This  electron transport chain of photosystem II helps the chlorophyll molecules in the plant leaves to tap the energy in the light photons. This energy is used to split a water molecule into hydrogen and oxygen atoms. The hydrogen is used to reduced carbon dioxide to make carbohydrates. Therefore, Atrazine stops photosynthesis by inhibiting the capacity of the plant to harness energy from sunlight for photosynthesis.

answer; ///i believe the answer your looking for is (ribosomes);

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.