Flashcards in Phys: Renal Deck (45)
what are the main functions of the kidney?
acid base balance
what is the functional unit of the kidney?
explain the kidney:
it is an excretory organ with an ENDOCRINE fxn.
it has 2 parts:
what are the 2 types of nephrons? how many nephrons in thebody?
nearly 1 million nephrons in the body. Cannot be regenerated.
what makes up the nephron?
Glomerulus- enveloped in a double layer Bowmans capsule
Two convuluted tubules- proximal & distal
two parts of the Loop of henle- two parts a thick and thin ascending, and a thin descending
what are the 2 hormones that are secreted by the kidney?
what hormones act on the kidney?
the kidneys function is dependent on?
how much does the kidney use of the cardiac out put?
20% (1 liter/min)
how much of the renal blood flow is the renal PLASMA flow?
60% (600 mL/minute)
course of blood flow in the kidney?
Renal art> interlobar> arcuate> interlobULAR> Afferent arteriole (in)> Glomerulus> Efferent arteriole (out)> peritubular cap.> Venules> interlobUlar vein> Arcuate vein> interlobar vein> renal vein> IVC
collecting duct> Calyx> renal pelvis> Ureter> bladder> urethra
how much do you filtrate a day?
purpose of bowmans capsule?
filtration due to fenestrations
pressure is -18 mm Hg
it pushes water back into the capillary
proximal tubule fxn?
100% of AA & glucose are filtered here
80% of bicarbonate & phoshate
60-70% of Na+ (exchanged for H+), Ca++, K+
50% H2O and urea
cells that form filtration membrane
loop of henle fxn?
vasa recta are?
thin-walled vessels, parallel loop of henle
distal tubule does?
aldosterone works here to reabsorb Na+ and secrete K+
reabsorption of filtrate in prox. tubule? distal tubule?
65% end of prox.
99% end of distal
what is the normal GFR?
determined by hydrostatic pressure
what does hyrdostatic pressure?
pushes water out of the capillary (+60 mm Hg)
what does oncotic pressure do?
pulls water back into capillary (-32 mm Hg)
what is the renal threshold for glucose?
180 mg/dL- once reached glucose will pass through the urine
what is the thin descending loop of henle permeable to?impermeable? purpose?
P: concentrate the urine
what is the thick ascending part impermeable to? purpose?
it is the diluting segment of the loop
what are juxtaglomerular cells for?
mechanoreceptors for BP entrance afferent arteiole
what are macula densa for?
chemoreceptors for JG cells
sensitive to Na+ conc.
located in the DCT
Aldosterone is from? purpose?
from Zona Glomerulosa
absorbs Na+, excretes K+
results from RA system
renin is from? stimulated by?
stim. by dec. in pressure in afferent arterioles
why is the RAA system stimulated? explain
drop in BP
Renin-Angiotensin- Aldosterone system
Angiotensinogen- protein produced in liver
Renin- enzyme made by JG cells
Angiotensin I- travels in blood
ACE- made in lungs (converts angio I into angio II)
Angiotensin II- constricts BV (inc. BP), stimulates release of- Aldosterone- inc. bp by inc. Na+ reabsorption
angitoensinogen> angintensin I
angiotensin I> angitensin II
respiratory acidosis is? cause? compensate?
inc pCO2 & dec pH
HYPOventilation: COPD & CHF
renal: inc H+, inc HCO3-
respiratory alkalosis is? cause? compensate?
dec. pCO2 & inc pH
renal: dec. H+, dec. HCO3-
Metabolic acidosis is? cause? compensate?
dec. HCO3-, dec. pH
diarrhea, diabetic ketoacidosis, renal dysfx, Aspirin overdose
metabolic alkalosis is? cause? compensate?
inc. HCO3-, inc pH
drugs, vomiting, diuretics: conns disease
what does ADH do?
increases water perm in the collecting ducts by acting on the aquaporins
secreted by supra-optic nucleus in the hypothalamus
what does ANP do?
decrease Na+ reabsorption in the DCT; results in increased urine ouput
peptide hormone produced in the atrial myocardial fibers
what does 1,25 dihydroxycarboxylase do?
acts on DCT by increasing Ca++ absorption
it is the active form of Vit. D
what is the pH of the blood?
what is volatile acid?
produced when CO2 reacts with h2O to form carbonic acid
what are examples non-volatile acid?