Urine hypertonic to the blood?

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darkhope

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Hi guys, so i was looking at a study review, and it states that the primary function of the nephron is to create urine that is hypertonic to the blood? But I don't get that, because urine is supposedly so concentrated to limit water loss so how can urine be hypertonic to blood if its so concentrated...shouldn't it be hypotonic instead...i'm so confused...

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Hypertonic means it has a bunch of crap in it. Your logic is right, you're just mixing up your terms
 
Hi guys, so i was looking at a study review, and it states that the primary function of the nephron is to create urine that is hypertonic to the blood? But I don't get that, because urine is supposedly so concentrated to limit water loss so how can urine be hypertonic to blood if its so concentrated...shouldn't it be hypotonic instead...i'm so confused...

Simply put, hypertonic means it has higher solute amount. When it says so concentrated means it has higher solute concentration than the blood and thus it is hypertonic to the blood since the blood has lower solute content and higher solution.
 
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Water loss can be limited by hormones such as aldosterone and ADH. The membranes in the nephrons can be manipulated to lose solutes, water, or both. Whether the urine is hyper or hypo to its environment doesnt matter if there is an impermeable membrane between them.
 
Hi guys, so i was looking at a study review, and it states that the primary function of the nephron is to create urine that is hypertonic to the blood? But I don't get that, because urine is supposedly so concentrated to limit water loss so how can urine be hypertonic to blood if its so concentrated...shouldn't it be hypotonic instead...i'm so confused...

The best way to think of it...

The way the kidney is set up... specifically the transporters in the nephron allow for concentration of the urine. Plus the gradients help too. Here's a good animation.

http://www.cellphys.ubc.ca/undergrad_files/urine.swf
 
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