Lesson 1: A+P Of The GU System Flashcards
Kidney - Cortex
- Outer zone
- Contains glomeruli and tubes
- For urine production
Kidney - Medulla
- Inner zone
- Contains loop of henle and collecting ducts
- For urine contraction and collection
Kidney - Renal Pelvis
Continuous with proximal ureter
Kidney - Nephron
Glomerulus: collection of capillaries surrounded by Bowman’s capsule
Proximal convoluted tubules → loop of henle → distal convoluted tubules → collecting duct
Kidney - Critical Functions
- Urine production + elimination of metabolic wastes
- Maintenance of fluid and electrolyte balance
- Maintenance of acid base balance
- Blood pressure regulation
- Production of erythropoietin
- Activation of vitamin D
Glomerular Filtration
Blood flows into capillary network under pressure through Bowman’s Capsule
Large volumes of “primitive urine” created
Urine Concentration
Urine passes through tubules and is selectively reabsorbed
750 - 2000 mls/ day
PH 4.6 - 6.0
Constituents: water, urea, creatinine, electrolytes, mucous, minimal RBC/WBC
Ureters
- 24-30 cm long, 0.2 cm wide
- Begins at renal pelvis and terminates in bladder
- Entry at oblique angle prevents reflux
- Smooth muscle lined with transitional cell epithelium
- Delivery of urine via peristalsis
Bladder
- Smooth muscle lined with transitional cell epithelium
- Fixed base (bladder plate) with distendable body
- 300 - 600 mls capacity
- Trigone: triangular muscle at base of bladder that surrounds 2 ureters and urethral opening
Critical Functions:
- stretch + store urine
- contract + empty
Urethra
Male: 22cm average - long and curved
Female: 3.5 - 5.5 cm average - short and straight
Functions
- Waterproof seal during filling of bladder
- Sphincter for controlled opening/continence