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BIBLIOGRAPHY
Nephrons

The nephron is the part of the kidney that actually does the filtering of the blood. About 1 million nephrons are found in the cortex of the kidney. It is responsible for the reabsorption of water and salts. This is also where glucose is absorbed back into the body. The nephron is made up of many different parts including:

 

          Intralobular Artery – Blood from the cortex enters into the nephron.

   

    Afferent Arteriole – carries the blood to the Bowman’s capsule.

     

     Bowman’s Capsule – Containing the glomerous, where all of the filtration occurs.

    

Glomerous- A Twisted bunch of small tubes where the blood will pass through. This is semi-permeable to allow for the re-absorption of salts and water. There are hormones called Aldosterone that are secreted by the brain to tell the glomerous just how much water is needed in the blood supply. The glomerous only allows what is needed to be re-absorbed. The salts and water, as well as glucose needed is re-absorbed out of the glomerous, and the rest of the waste, including toxins, is excreted as urine. Only 1 thousandth of the blood circulating through your kidneys on any given day will be turned into urine.

       

      PASSAGE WAY FOR RE-ABSORPTION

        

Efferent Arteriole - If something is to be re-absorbed into the body, it will exit the bowman’s capsule using this arteriole.

      

  Medullary Plexus – A network of capillaries that take the filtered blood from the efferent arteriole to the intralobular vein.

 

 Intralobular vein – Takes filtered blood out of the nephron back into the kidney to be re-absorbed by the body.

 

THE PASSAGE WAY FOR THE URINE:

 

Renal Tubule:

Convoluted tubule – This is where the urine leaves the glomerous. It brings the urine to the Loop of Heinle. More re-absorption occurs in this tubule.

                              And…

Loop of Heinle – A U-turn in the tubule which also carries urine away from the nephron. This leads to the distal convoluted tubule.

 

Distal convoluted tubule – Brings urine along to the collecting duct.

 

Collecting Duct – Collects urine and passes it into calyces then to renal pelvis reservoir to be expelled down the ureters.

nephron2.gif

The Nephron!

This picture shows the Bowman'd Capsule encapsulating the glomerous, which are the wound up tubes in the "backwards C" like socket.  The intralobular artery and vein are also evident. They are the tubes that appear to be leading to the Glomerous. To the right of the Bowman's capsule, you see the series of tubules.

How The Wastes Come Out