Urea is produced when foods containing protein, such as meat, poultry, and certain vegetables, are broken down in the body. Urea is carried in the bloodstream to the kidneys, where it is removed along with water and other wastes in the form of urine.
How is urea transported to the kidneys?
The excretory system
Too much urea is toxic so the body must get rid of it. The urea is transported from the liver to the kidneys using the circulatory system. Here, urea is filtered out of the blood and ends up in the bladder as part of urine.
How does urea enter the blood?
Urea apparently permeates the red cell membrane via a facilitated diffusion system, which plays an important role when red blood cells traverse the renal medulla; rapid urea transport helps preserve the osmotic stability and deformability of the cell, and it helps prevent dissipation of extracellular osmotic gradients.
Where does urea in the body come from?
The liver produces several chemicals (enzymes) that change ammonia into a form called urea, which the body can remove in the urine.
Why is urea reabsorbed in the kidney?
The urea reabsorbed increases the medullary concentration of the solute, which is critical for the reabsorption of water from the thin inner medullary part of the descending limb of the loop of Henle. Here, there is no osmotic gradient to cause water movement in the diluting kidney.
How does urea get reabsorbed?
If you remember a couple of videos back we said that urea is actually reabsorbed a little bit throughout the nephron. But it's only reabsorbed a little and what I mean by a little is it's reabsorbed
How does urea get filtered?
Quote from video:
And it's dumped into the bloodstream. So urea molecules in the blood get freely filtered across the glomerular capillaries. And make their way through the renal tubule.