URO 1: Genitourinary system Flashcards
What are the functions of the kidney?
Excretions of metabolic products Excretion of foreign substances Regulation of body fluids, electrolytes and acid-base balance Control of blood pressure Secretes hormones
What is the blood supply to and from the kidney?
Renal artery Segmental artery Interlobar artery Arcuate artery Interlobular artery Afferent arteriole Glomerular capillaries Efferent arteriole Peritubular capillaries Interlobular vein Arcuate vein Interlobar vein Renal vein
What is the function of the detrusor muscle?
Contracts to build pressure in the urinary bladder to support urination.
What is the function of the trigone?
Stretching this region to its limits sends signals to the brain about the need for urination.
What is the function of the internal sphincter?
Involuntary control to prevent urination
What is the function of the external sphincter?
Voluntary control to prevent urination.
What is the function of the bulbourethral gland?
Produces thick lubricant which is added to watery semen to promote sperm survival/
What are the parts of a nephron?
Glomerulus Bowmans capsule Proximal convoluted tubule Loop of henle Distal convoluted tubule Collecting duct
What are the two types of cells in the collecting duct?
Principal and intercalated cells
What are the constituents of the juxtaglomerular apparatus?
Macula densa
Extraglomerular mesangial cell
Juxtaglomerular cells
What is the function of the juxtaglomerular apparatus?
GFR regulation through tubulo-glomerular feedback mechanism.
Renin secretion to regulate blood pressure.
What are the four different renal processes?
Glomerular filtration
Reabsorption
Secretion
Excretion
What drives fluid through the filtration process of the bowman’s capsule?
Hydrostatic pressure of the heart.
What are the three stages of filtration in the bowmans capsule?
- Fenestrae in capillary endothelium
- Glomerular basement membrane
- Slits between podocytes
What is the formula of net ultrafiltration pressure?
HPgc - HPbw - OPgc
What is the glomerular filtration rate?
Amount of fluid filtered from the glomeruli into the Bowman’s capsule per unit time.
What are the units of GFR?
mL/min
What is the normal GFR for healthy males?
90-140mL/min
What is the normal GFR for healthy females?
80-125mL/min
What is a fall in GFR the cardinal feature of?
Renal disease
What is the myogenic mechanism in the regulation of GFR?
- Arterial pressure increases
- Afferent arteriole stretches
- Arteriole contracts
- Vessel resistance rises
- Blood flow reduces
- GFR stays the same
What is the tubulo-glomerular feedback mechanism?
- Increase/decrease in GFR
- Increased/decreased NaCl in loop of henle
- Change detected by macula densa
- Increased/decreased ATP and adenosine discharged
- Afferent arteriole constricts/dilates
- GFR stabilizes
What is renal clearance?
The number of litres of plasma that are completely cleared of the substance per unit time.
What is the formula for renal clearance?
C= (U x V)/ P
