Zoe McCarthy
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Urinary System in Context
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Urinary System in Context
System
How does it do it?
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Functions of the Urinary system
• 1. Regulating blood volume and pressure
• 2. Regulating plasma concentrations of sodium, potassium, chloride and other ions
• 3. Stabilising blood pH
• 4. Conserving nutrients
• 5. Detoxifying poisons (with the liver)
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Organisation of the Urinary System
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Kidneys
Ureters
Urinary bladder
Urethra
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Position of the Kidneys
CT abdomen with contrast
MRI coronal abdomen
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Protection of the Kidneys
• 3 layers of connective tissue: Renal cortex
– Inner layer- Renal capsule
– Middle layer- Adipose capsule – Outer layer-Renal fascia
Retroperitoneal space
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Surface anatomy of the Kidney
• Hilum is located on the medial surface
10 cm
3cm
5.5cm
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Internal Structure of the Kidney
Renal Lobe
Renal pyramids
Renal papilla
Renal Columns
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Microscopic structure of the Kidney and Urine Production
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Renal Corpuscle and Filtration
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Nephron-Tubular System
1. Proximal convoluted tubule 2. Descending loop of
Henle
3. Ascending loop of
Henle
4. Distal convoluted tubule 5. Collecting duct
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Summary so far…..
Blood enters the kidney through the renal artery at the site of the hilum
The PCT is concerned with reabsorption- organic nutrients are reabsorbed and water follows because there is a concentration gradient The remaining filtrate moves into the descending loop of henle. This is lined with thin cells so water moves out
A number of other nephrons join up to the cleectig duct which travels through the medulla to the renal papilla wher the filtrate is emptied in the minor calyx
4-5 minor calyces join up to make a major calyx
The renal artery divides in to ever smaller arteries and arterioles The filtered substances move into the proximal convoluted tubule
Because water has been reabsorbed the concentration of the filtrate is not very high
From the DCT the filtrate