How does the kidney help in regulating the pH of our body?

The kidneys provide a slower but more powerful means to regulate pH. They excrete or absorb hydrogen ions (H+) and bicarbonate ions (HCO 3-) which is necessary for adjusting pH of blood.

Kidney Filtration & Urine Formation

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Physiology of Excretion

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Physiology of excretion

Kidneys filter all of the blood that comes from the heart. The process of cleaning takes place in the nephrons present in kidneys in three stages. They are ultrafiltration, reabsorption and tubular secretion.

The nephron cleans all your body blood in 45 minutes. Everyday nephron sends about six cups of urine to the urinary bladder. The main components of urine are water and urea.

1.0Ultrafiltration

The first step in clearing the blood is filtration under pressure, the passage of a liquid through a filter to remove impurities. Filtration occurs in the glomeruli. Blood pressure helps plasma (the liquid portion of the blood) to pass through the capillary walls in the glomerulus. Glomerular capillaries are more permeable than other capillaries. The filtrate contains water, glucose, amino acids, ions and urea.

Normally in a healthy adult, the initial filtrate in the kidneys is about 180L daily. However, the volume actually excreted is only a liter or two a day because the remaining filtrate is reabsorbed in the renal tubules.

3.0Tubular secretion

The passage of unwanted substances out of the capillaries directly into the renal tubules is called as tubular secretion. This is an additional way of getting waste materials into the urine.

In Winters

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less sweating

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More blood volume

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Less conc. of ADH

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Less permeability of DCT

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Less reabsorption of H₂O into blood capillaries

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More urine formed

In Summers

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More sweating

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Less blood volume

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More conc. of ADH

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More permeability of DCT

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More reabsorption of H₂O into capillaries

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Less urine formed

4.0Also Read

Reproduction	Artificial Kidneys or Hemodialysis	Post Fertilization Changes in the Flower
Human Male Reproductive System	Reproduction in Plants	Endocrine Glands
Human Female Reproductive System	Pollination and Fertilization in Plants	Movement in Plants