Urinary = Filters blood
* Pathway: Kidney → Ureter →
→ Bladder → Urethra
* Maintains H2O & Solute balance
Renal Exchange Processes
4 FACTORS ASSOCIATED W/
RENAL EXCHANGE
[1] Glomerular Filtration
[2] Reabsorption
[3] Secretion
[4] Excretion
NEPHRON: Fx UNIT
[1] Glomerular
[2] Prox. Convoluted Tubule (PCT)
[3] Descending Loop
[4] Loop of Henele
[5] Ascending Loop
[6] Distal Convoluted Tubule (DCT)
[7] Convoluted Duct (CD)
GLOMERULAR FILTRATION (GFR)
* Filtration = Removal of Lg. amt.
of Urea
* Increase GFR → More substances
are lost in the urine (decrease
change of reabsorption)
* Decrease GFR → Waste is
reabsorbed (moving so slow that
waste is reabsorbed)
GLOMERULAR REGULATION
* Extrinsic (maintain systemic B.P.)
* Neural
* Baroreceptors
* SNS
* Hormonal = RAA System
(Renin-Angiotensin)
* Intrinsic (maintain GFR regardless
of B.P.)
* Affects size of diameter
ARTERIOLE DIAMETER
* Afferent (IN) → Incr. Dia. = Incr. GFR
Decr. Dia = Decr. GFR
* Efferent (OUT) →
* Incr. Dia = Decr. Filtration Pressure
* Decr. Dia = Incr. Filtration Pressure
* Pressure
* Incr. pressure = Incr. fluid in blood
(body tries to get rid of excess fluid
with increased urine formation)
Nephron Functional Unit
Urinary System: Order of Progression
NEPHRON REABSORPTION
* H2O -> [1] PCT; [2] DCT/CD
* Na+ -> [1] Aldosterone (reabsorbs Na+);
[2] ANP (inhibits Na+)
* K+ -> Aldosterone
* Ca+ -> [1] Organs = Kidneys, G.I. Tract,
Bone, Skin
[2] Hormones = Parathyroid,
Calcirtrol, Calcitonin
* Kidneys -> Bicarbonate = pH levels
[1] Lungs (CO2)
[2] Kidney (Bicarbonate)