Download Unit 5 Notes: Basic Urinary Anatomy & Function

Unit 3 Notes:
The Urinary/Excretory
System
(1) Main Organs
•Kidneys
•Ureters
•Bladder
•Urethra
(2) Functions
• Filter blood
• Remove impurities, toxins,
excess nutrients
• Reabsorb needed water +
nutrients
(3) Ureter, Bladder &
Urethra Function
• Ureters:
Tubes which carry filtered “liquid waste” towards
the bladder.
• Bladder:
Storage tank for filtered “liquid waste”.
• Urethra:
Tube which allows filtered “liquid waste” to exit
body.
(4) Nephrons
• The nephrons are the filtering units inside the kidneys.
• 2 Main Structures:
– Glomerulus  Bundle of capillaries w/ blood to be
filtered.
– Renal Tubule  Tubes following capillaries, which
collect filtered contents
• Bowman’s CapsulePortion of tubule where initial
filtration and absorption occurs
(5) Urine Formation Steps
1- Filtration:
– Water + Small Solutes are forced through capillary walls
into Bowman’s Capsule.
2- Reabsorption:
– Water, Glucose, Amino Acids & Ions that were filtered
out are actively transported back into capillaries and
blood.
3- Secretion:
– H ions, K ions, urea, and drugs/toxins are forced through
capillary walls into renal tubule.
(6) Regulating Drops in
Blood Pressure
• Antidiuretic Hormone (ADH) from Pituitary:
– Increases water reabsorption from renal tubule.
• Aldosterone from Kidney:
– Increases water retention in blood by reabsorbing
more sodium from renal tubule.
• Angiotensin II from Blood:
– Causes vasoconstriction, increasing blood
pressure.
(7) Don’t Pee It Out…
• Glucose  Chill out on sweets OR Diabetic?!
• Protein  Increased Physical Activity &
Pregnancy OR Hypertension & Nephron
Disease?!
• Pus  Urinary Tract Infection
• Blood  Kidney Stones, Infection, Trauma,
Anemia ?!
• Bile  Liver Disease?!
(8) Kidney Dialysis
• Used in hospitals when kidneys fail (stop working)
• Blood is filtered through mechanical pump +
tubing which regulates contents
• Causes for Kidney Failure:
– Repeated kidney infections
– Physical Trauma
– Heavy Metal / Chemical poisoning
– Low Blood delivery (arteriosclerosis)