Buffers, lungs and kidneys maintain blood pH between 7.35 and 7.45.
Bicarbonate buffer: CO2 + H2O ⇌ H2CO3 ⇌ H+ + HCO3-. Lungs adjust CO2 within minutes; kidneys excrete H+ and regenerate bicarbonate over hours to days. Acidosis and alkalosis may be respiratory or metabolic.
Respiratory compensation is fast; renal compensation is slow. Arterial blood gas tests assess status.
Key idea: pH must stay within 7.35 to 7.45 for enzymes to work.
Buffers, lungs and kidneys maintain blood pH between 7.35 and 7.45.
Acid-Base Balance is one of the 51 topics in Human Physiology. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Excretory System, Renal Autoregulation, Respiratory System.
Hyperventilation causes respiratory alkalosis.
Work through the Beginner topics in Human Physiology first, such as Homeostasis, Tissues and Organs, Skeletal System, then return to Acid-Base Balance. Advanced topics assume the Intermediate vocabulary.
The closest topics to Acid-Base Balance are Excretory System, Renal Autoregulation, Respiratory System, Renin-Angiotensin-Aldosterone System. Comparing them side by side is a good way to see how the ideas connect.
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Acid-Base Balance. To practise the whole of Human Physiology, use the Human Physiology quiz.
Acid-Base Balance: Buffers, lungs and kidneys maintain blood pH between 7.35 and 7.45. Excretory System: Kidneys, ureters, bladder and urethra remove metabolic waste and balance water. Read both side by side and note what each one explains.
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Excretory System and explain the difference aloud. Finally, take the Human Physiology quiz and come back to this page for any question you miss.
Kidneys, ureters, bladder and urethra remove metabolic waste and balance water.
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❤️ Human Physiology