3 12 the excretory system n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
3.12 The Excretory System PowerPoint Presentation
Download Presentation
3.12 The Excretory System

Loading in 2 Seconds...

play fullscreen
1 / 26

3.12 The Excretory System - PowerPoint PPT Presentation


  • 76 Views
  • Uploaded on

3.12 The Excretory System. Pages 210-214. Kidneys. The kidney is the size of a fist and a mass of approximately 500 grams. Metabolic Waste. Waste is produced from the break-down of proteins. Deamination. We eat protein. We use protein for building and repair.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about '3.12 The Excretory System' - ban


Download Now An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
kidneys
Kidneys
  • The kidney is the size of a fist and a mass of approximately 500 grams.
metabolic waste
Metabolic Waste
  • Waste is produced from the break-down of proteins.
deamination
Deamination
  • We eat protein.
  • We use protein for building and repair.
  • The liver breaks down extra protein.
  • The amino group, NH2 , is converted to ammonia, NH3 ,
toxic
Toxic
  • The amino group, NH2 , is converted to ammonia, NH3
  • Ammonia is toxic! 0.005 mg can kill you!
solution
Solution…
  • Combining ammonia with carbon dioxide makes urea, [NH2]2CO
  • Urea is less toxic than ammonia
  • The blood carries urea to the kidneys where it is excreted in the urine
kidneys1
Kidneys
  • Filter blood
renal arteries
Renal arteries
  • Bring blood to the kidney.
renal veins
Renal Veins
  • Return “cleaned” blood to the circulatory system.
ureters
Ureters
  • Carry urine from

the kidneys to the

Bladder.

bladder control
Bladder control
  • A sphincter at the base controls the bladder
  • 200 mL …signal sent “Go to the bathroom”
  • 400 mL …urgent signal sent “ Go to the bathroom right now!”
  • 600 mL …too late
ureter
Ureter
  • The tube that carries urine from the bladder to the exterior of the body.
urine formation
Urine formation
  • Step #1 filtration
  • Step #2 reabsorption
  • Step #3 secretion
nephrons
Nephrons
  • One million per kidney
bowman s capsule
Bowman’s capsule
  • The cup-like structure that surrounds the glomerulus.
the glomerulus
The glomerulus
  • Cluster of capillaries
  • The area of fluid filtration
proximal tubule
Proximal tubule
  • a hollow, winding large diameter tube
  • for the reabsorption of glucose, sodium, amino acids
  • these are pumped back into the capillaries
  • urea stays in the tube
descending loop of henle
Descending loop of Henle
  • Straight part of the loop moving away from the proximal tubule
  • Water flows out by osmosis
ascending loop of h enle
Ascending Loop of Henle
  • Straight part of loop heading to distal tubule
  • Sodium pumped out of tube
distal tubule
Distal tubule
  • A hollow winding large diameter tube.
  • Reabsorption of water if needed.
collecting duct
Collecting Duct
  • System of urine collecting ducts that widen as they near the renal pelvis
  • Wastes are transferred from the capillary network to the duct.
  • Water moves by osmosis from the duct to the surrounding blood.
1 filtration
#1 Filtration

Moves from glomerulus to Bowman’s capsule:

  • Water
  • Salt
  • Glucose
  • urea
1 filtration1
#1 Filtration

Does not move from glomerulus to Bowman’s capsule:

  • Plasma proteins
  • Blood cells
  • Large platelets
volume
volume
  • 600 mL blood through each kidney per minute
reabsorption
Reabsorption
  • 119 of every 120 mL of fluid is returned to the blood
urine
Urine
  • 95% water
  • 5% salts, urea etc.