lesson17.notebook
Review:
February 26, 2013
Diagram of a Nephron
­ organs of excretory system
­ parts of the kidneys
­ what the kidneys do
May 14­10:08 AM
May 14­10:30 AM
How the Kidneys Filter Blood: (How a Nephron Works)
1 Blood enters the Bowman's capsule through the renal artery which branches to form the glomerulus
2. Blood pressure forces blood plasma and small particles (called nephric filtrate) into the surrounding capsule (Bowmans Capsule)large particles remain in the blood
May 14­10:09 AM
May 3­8:34 AM
3. The nephric filtrate moves into the proximal tubule where material needed by the body is reabsorbed into the blood. 4. Reabsorption in the proximal tubule occurs due to osmosis, diffusion, and active transport which remove 99% of the water, glucose, amino acid and ions (all returned to the blood)
NOTE: The proximal tubule contains small villi which speed up the reabsorption process
May 3­8:05 AM
May 3­8:35 AM
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lesson17.notebook
February 26, 2013
5. The filtrate leaves the proximal tubule and enters the loop of Henle. In the loop of Henle there is an increase in the sodium concentration in the surrounding cells and this causes water to be removed by osmosis (in the descending tubule)
6. The ascending tubule is impermeable to water so sodium ions diffuse out in this section
May 3­8:05 AM
7. Filtrate moves to the distal tubule where tubular secretion occurs. Active transport pulls hydrogen ions, creatine, drugs such as penicillin out of the blood into the filtrate
May 3­8:41 AM
Label the following:
8. Fluid from a number of nephrons moves from the distal tubule to a common collecting duct which carries urine to the renal pelvis
May 14­10:24 AM
May 14­10:32 AM
Readings:
Refer to handout provided:
Pages 374 ­ 377
See Diagram page 377
Kidney Disorders:
Kidney Action: ­ UTIs
­ Kidney Infections
­ Kidney Stones
­ Artificial Kidney Dialysis
­ Kidney Transplant
http://www.youtube.com/watch?v=cIp2OLPiosE
http://www.youtube.com/watch?v=CDBNmgkIqMs&feature=related
May 14­10:39 AM
May 14­10:45 AM
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