FINAL EXAM-Ch.14 Flashcards
(24 cards)
Kidney Functions
- Filter toxins, metabolic wastes, excess water and ions from blood
- Filtrate will be formed into urine
- Return any needed substances from filtrate to blood
Hilum (Hilus)
- Renal artery and renal vein and renal nerves enter and exit the kidney
- Renal Pelvis
Renal Pelvis
attaches; superior expanded region of ureter
What is in renal medulla, renal cortex, and renal sinus
Renal Cortex: Superfical, granular and ligher in color
Renal Medulla: Deep, darker in color, striated (nephrons) and has conshaped masses (pyramids)
Renal sinus: filled space that contains vessels, nerves, fat, calyces (calicoes) and renal pelvis
Renal pyramid
contain nephrons and urine collecting tubules
1st step of urine production
Filitration: blood filtrate leaves kidney capillaries and enters tubule lumen
2nd step of urine production
Reabsorption: ions, nutrients, water recovered from filtrate and returned to the blood by capillaries
3rd step of urine production
Secretion: nay additional substances from blood that have not been included in the filtrate are moved into the tubule lumen to be included in the final filtrate
4th step of urine production
Excretion: execration of urine from the body
Glomerular Capillary
(associated with nephrons)
NOT A REGULAR CAPILLARY
- specialized for filtration
- allows the blood pressure in the capillary beds to be very high
- forced clid and solute out of the blood into the glomerular capsule
Peritubular Capillary
(associated with nephrons)
where most of the filtrate is reabsorbed fro the renal tubules and returns to the blood
Podocytes
“foot cells” that cover the surface of the capillaries
-Foot processes extend from them creating gaps (filtration slits or slit pores or slit diaphragms)
Hold back some of smaller protein
How Glomerular Filtration Works
liquid components of the blood are filtered from glomerulus into the glomerular capsule.
It is a passive process
- Hydrostatic pressure force the fluids and solute through a membrane
- The glomeruli more efficient filter than other capillary beds
- Filtration membrane is a large surface area and very permeable
Onconic/ Osmotic Pressure
During filtration it is important to keep the plasma proteins in the plasma
-Maintain osmotic (oncontic) pressure
Oncotic pressure will tend to pull water into the circulatory system
Blood cells or protein in urine signal what?
There is a problem with the filtration membrane.
Common with diabetes and hypertension.
Signals kidney damage. If untreated will profess to end stage renal disease and renal failure.
Starling Equation
net fluid movement of hydrostatic pressure greater than onconic pressure or other way around.
What happens in each section of the nephron when Reabsorption occurs?
Proximal Tubule: solute and water reabsorptions occurs.
Loop of Henle: Descending limb is critical for water reabsorption. Ascending limb solutes are recovered
Distal Tubule: hormone mediated regulation of uptake of solutes and water
Secretion.
Active transport.
Substances such as hydrogen and potassium ions, and organic anions move from the peritubular capillary blood into the tubular lumen filtrate (urine)
Proximal Tubule Cell Type
mainly composed of cuboidal cells
Loop of Henle cell types
- first section composed of cuboidal cells
- second section (halfway down) descending loop transition to squamous cells
- becomes cuboidal again in ascending loop
Distal Tubule Cell Types
composed of specialized epithelial cells-principle cells
- some regions will have no microvilli
- some regions will have intercalated cells with some microvilli
What transports in each part of the Loop of Henle
- descending limb is permeable to water and less impermeable to salt
- ascending limb is impermeable to water. uses countercurrent exchange mechanism to actively pump sodium out of the filtrate
Distal Tubule
Distal tubule is hormone regulated, also secretes hydrogen and ammonium to control pH
Collecting Duct
Final effort to conserve water.
