Renal system Flashcards
What is the function of the kidneys?
How much cardiac output does the urinary system receive?
20-25%
What are nephrons?
What are the vascular components of the renal system?
What are the tubular components of the renal system?
What are the 4 processes of the kidney?
Explain the process from the proximal tubule to the collecting duct
Explain the process of filtration
-Cardiac output is 5L/min
-Kidneys receive about 20% of CO (1L/min)
-60% of blood is plasma (0.6L/min)
-20% of the plasma is filtered (0.12L/min)
-0.12L/min x 60min/hour x 24 hour/day
about 173 (180) L plasma filtered/day
-125ml/min
What is the renal corpuscle (Triple filtration barrier)
What are the 3 pressures that govern filtration from glomerular capillaries into the renal tubes?
What is GFR and the two factors that influence it?
Why is GFR relatively constant?
-Prevents excess fluid loss during increased activity, blood pressure, etc.
-Doesn’t regulate at low pressure to allow increased filtration
explain the effects of GFR and RBF when each afferent and efferent arterioles are constricted/dilated seperately
Explain GFR myogenic autoregulation
Explain tubuloglomerular feedback
How do sympathetic neurons influence GFR
How do hormones influence GFR
How can you calculate the amount filtered/reabsorbed/secreted in the kidneys
Describe reabsorption
Describe transport during reabsorption
Explain active transport of Na+ during reabsorption
Explain passive reabsorption and endocytosis
Explain how renal transport can reach saturation
Describe renal threshold
Explain how peritubular capillary pressures favor reabsorption
What is secretion?
Explain the secondary and tertiary indirect active transport process of secretion
What is clearance
What is excretion?
Explain how clearance is used to noninvasively measure GFR
How is creatinine clearance used as a measure of GFR?
plasma creatinine concentration is quite stable, it is filtered, not reabsorbed, but a very small amount is secreted, so it slightly overestimates GFR
How does clearance help determine net renal handling?
Explain renal clearance of glucose
Explain renal urea clearance
Explain renal penicillin clearance
Summarize the relationships between GFR vs Clearance and their respected outcomes of renal handling
What is the micturition reflex?
What is incontinence?
Describe the physiological responses to increase volume of fluid in the bladder that leads to micturition reflex
