What does the respiratory system eliminate when there is an excess of hydrogen ions in the body?

by breaking down carbonic acid into carbon dioxide and water.

The carbon dioxide is expelled from the body

Explanation:the body is able to maintain a constant internal environment through hoemostatis.one of such control is the acid-base balance in the body.

It does this by regulating the amount of hydrogen ions in the blood.A low pH indicates an acidic condition and a high pH indicates an alkaline condition.

The human blood has a pH of 7.35---7.45.it is slightly alkaline and needs to keep this range constant.

The lungs and kidneys involved in regulating the body pH.

When there is excess hydrogen ion in the blood, bicarbonate ions combine with the hydrogen ions to form carbonic acid . this carbonic acid breaks down into water and CO2 .the co2 is expelled from lungs through gaseous exchange.

When the accumulation of acid in the blood is high,the pH drops below 7.35 and this is called respiratory acidosis.

When there is excess alkaline in the blood,the pH goes beyond 7.45 and this is called respiratory alkalosis.

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.