How might the allele that causes a disease stay in the population if it is fatal to those who have the disease

A way a disease that is fatal can stay in the population is if its hereditary. Such as, it allows the carrier to live long enough to have children, which have the chance to either get it, or pass it on to their children.

Hope this helps!

Explanation:

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.

there's the proffessional site that will you.