ADH Diagram Animated

7/28/2019 ADH Diagram Animated

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Water contentof the blood normal

Water content of

the blood HIGHWater content of

the blood LOW

Too much water drunk

Too much salt

or sweating

Brain

producesMore ADH

Urine output

LOW

Brainproduces

Less ADH

Urine output

HIGH

High volume of water

reabsorbed by kidney

Low volume of water

reabsorbed by kidney

(small volume of

Concentrated urine)

(large volume of

dilute urine)


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Click on the screen

icon below to run thetutorial

(then click the mouse button to

make it play through)


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All land animals need to conserve water.

This is because the external environment is usually

drier than the internal environment of the animals

body. Thus, water will tend to diffuse away from the

body.

There is also a need to excrete waste products such

as urea, which is dissolved in water. This creates aproblem!

In mammals, the kidneys are responsible for both excretion of

urea andosmoregulation (the control of body fluid

concentration).

So, the kidney must balance the need to excrete with the need

to conserve water, in other words it must produce a small

volume of highly concentrated urine.


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The operating unit of the kidney is called the

nephron.

There are about 1 million nephrons in each of

the 2 kidneys.

Each nephron comprises 5 segments:

Glomerulus

Proximal (first) convoluted tubule

Loop of Henle

Distal (second) convoluted tubule

Collecting duct

The Loop of Henle allows mammals to produce

urine which is more concentrated than body

fluids...


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Cortex

Medulla

The nephrons are packed into the kidney:

the glomeruli and convoluted tubules in the cortex,

the loops and collecting ducts extending into the medulla.

All the collecting ducts eventually join up to form the ureter,

emptying urine into the bladder and away!

Ureter


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CortexWater leaves - ion

concentration in

filtrate increases

Filtrate reaches maximum concentration

Chloride ions out

(sodium follows) -

ion concentrationin filtrate decreases

Medulla


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To ureter

Collecting duct Several nephrons

empty into one

collecting duct.

The collecting duct

passes through the

progressively more

concentrated medulla,

losing water byosmosis. This water

is reabsorbed by the

capillaries.

This water is

conserved, and a

highly concentrated

urine is produced.

Water reabsorbed into vasa recta,

urine becomes more concentrated

Cortex

Medulla


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Now test yourself

Be warned - this test requires you

to understand everythingthat goes

on in the nephron

Not for the faint-hearted!

(if the test doesnt appear straight away,

click on Reload)
http://localhost/var/www/apps/conversion/tmp/scratch_10/loopquiz.htmhttp://localhost/var/www/apps/conversion/tmp/scratch_10/loopquiz.htmhttp://localhost/var/www/apps/conversion/tmp/scratch_10/loopquiz.htmhttp://localhost/var/www/apps/conversion/tmp/scratch_10/loopquiz.htm

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ADH Diagram Animated