Kidney Anatomy Flashcards
Compenents of the urinay system
Kidneys
Ureters
Urinary bladder
Urethra
Prostate (men)
Kidney functions (3)
- Maintain fluid and electrolyte homeostasis
- Rid the body of water soluble wastes via urine
- Three important endocrine functions:
Produces erythropoietin- stimulates RBC production
Activates Vitamin D
Produces renin, which helps regulate blood pressure
Kidney anatomy
- Located in the retroperitoneal space
– Assess at the costovertebral angle (CVA) - Each kidney contains > 1 million nephrons
– The nephron is the functional unit of the kidney
– We can function with 10-25% of nephrons
– This is why living humans can donate 1 kidney
Renal pelvis
Large collecting area for urine that drains from the nephrons
Medulla
– Contains 8-12 pyramids that consist of:
* Collecting tubules
* Collecting ducts
* Loops of Henle & capillaries
Renal cortex
Contains all glomeruli and 85% of nephron tubules
Kidney blood supply:
How much cardiac output is delivered to the kidneys?
Total kidney blood flow?
1/4 cardiac output delivered to kidneys
1200 mL/min total kidney blood flow
Function of the nephron:
- Each nephron has a glomerulus and a tubule
-Filter water-soluble substances from the blood
-Reabsorb filtered nutrients, water, and
electrolytes
-Secrete wastes and excesses
Function of the glomerulus:
– Filters fluid from the blood into tubules
– Prevents passage of RBC’s and proteins
– Surrounded by a Bowman’s capsule
– The overall glomerular filtration rate is about 125
mL/min
Ureters structure and function
- Two Ureters
– Narrow tubes, 10-12 inches long
– Drain urine from renal pelvis to bladder
Bladder structure and function
– Reservoir for urine
– Normal output is 1500 mL/day
Urethra structure
– Small muscular tube from bladder neck to meatus
– Female = 1-2 inches; Male = 8-10 inches long
