Urinary System Flashcards
What makes up the urinary system?
Upper urinary tract
- Kidneys and ureters
Lower urinary tract
- Bladder and urethra
What are the functions of the kidneys?
Urine formation
- Filter -1200mL of blood/minute
- Regulates levels of fluids and electrolytes
- Removes metabolic wastes, drugs and toxins
Endocrine and metabolic functions
- Erythropoietin: blood cell production
- Renin: blood pressure regulation
- Vitamin D: converts inactive form (cholecalciferol) to active form (calcitriol)
- Gluconeogenesis: formation of glucose from non-carbohydrate sources
What are the structures entering the hilum?
Renal vein
Renal artery
- Accompanied by autonomic nerves and capsular lymphatics
Renal pelvis
- Funnel-shaped beginning of the ureter
Where are the kidneys located?
T12-L3
Lie obliquely in paravertebral gutters
Rt kidney crowned by liver and sits lower than Lt
- Rib 12 overlies upper pole of rt kidney
- Rib 11 overlies upper pole of lt kidney
What is the vertical ROM of the kidneys?
About 2cm (during full respiratory excursion of the diaphragm)
Are the kidneys intra or retro peritoneal?
Retroperitoneal - kidneys lie on the posterior abdominal wall (anterior aspect covered by parietal peritoneum)
What is the gross internal structure of the kidneys?
Cortex
- Beneath capsule
Medulla
Renal pelvis
How is the medulla arranged?
As pyramids (cone-shaped masses) that have papilla and base
Pyramids: striped appearance due parallel bundles of urine collecting tubules
Renal columns: inward extensions of cortical tissue that separate the pyramids
Pyramid + surrounding cortical tissue = kidney lobe
How is the renal pelvis arranged?
Urine drains from papillae of the renal pyramids into several minor calyces
Minor calyces converge to form 2-3 major calyces
Major calyces empty into the renal pelvis
- A funnel-shaped expansion continuous with the ureter leaving the hilum
What are the kidney poles and surfaces?
Lateral border - convex
Medial border - concave, has a vertical cleft (renal hilum) which extends into an internal cavity (renal sinus)
What are the structures entering the hilum anterior to posterior?
Renal vein
Renal artery accompanied by autonomic nerves and apsular lymphatics
Renal pelvis (funnel-shaped beginning of the ureter)
What is the arterial supply of the kidneys?
Renal arteries
What is the venous drainage of the kidneys?
Renal veins
Where do the renal arteries arise from?
Aorta at the level of L1/2 IVD
Which renal artery is longer?
Right renal artery
What happens when each renal artery enters the renal sinus?
Divides into smaller branches
What forms each renal vein?
5-6 interlobar veins that unite at the hilum
Which renal vein is longer than the other?
Left longer than right