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When walking at 5 km per hour the amount of oxygen used is 3 litres per minute.
The volume of air of each breath is 3.0 litres. Air contains 20% oxygen of which the
body uses 20%. Use this information to calculate how many breaths per minute a
person would take when walking at 5 km per hour. Show your working out

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.

the glands which are associated with each description is given below: