Wk 10- The Renal System Flashcards
What are the 4 pain organs/ tissues of the renal system?
- K? x2 = active renal organs
- Ur? x2 = urine > bladder
- B? = ? storage
- U? = ? disposal
- Kidneys
- Ureter
- Bladder
- Urethra
The kidneys:
Main functions ~ Removal of w? R? of fluids / e? Regulation ?h Maintain blood ? Control erythropoiesis ( ? blood cells)
Waste Regulation , electrolytes Ph Pressure Red
The kidneys:
10-12 cm long
Renal cortex = o? region kidneys , contains n?
Renal medulla= inside kidneys, renal py? separated by renal c?
Outside , nephrons
Pyramids, columns
Kidneys:
Kidneys remove w? and regulate composition of b?
1200 ml blood /?
Represents 20-2?% cardiac output
Path of blood in the kidney = A? artery in , E? artery out for filtration
Waste, blood
Minute
25%
Afferent in, efferent out
The nephron:
F? unit of the kidney
Renal corpuscle =
Glomerulus (ca? network)
Glomerular capsule (Bo? capsule)
Renal tubule =
Tubes conveying fil?
Functional
Capillary network
Bowman’s capsule
Filtrate
The nephron:
Each kidney has ?.25 million Nephrons
Cortical nephrons = 80-??% of all nephrons
Short nephron loops (loops of h?)
Juxtamedullary nephrons = extend into the m? , long nephron loops
1
85%
Henle
Medulla
Nephrons:
Contain capillary network of the gl? The capillaries are covered by Po? and Ped? cells
Re? and secretion take place across t? walls
Glomerulus , podocyte , pedicel
Reabsorption , tubular
The Nephrons:
What are the 3 nephron functions?
- Glo? filtration = w? and solutes in plasma cross filter surface
- T? re? = ??% water and useful solutes return to b? via peri tubular capillaries and vasa recta
- T? secretion = secretion of wastes, t? and ions from peri tubular capillaries
- Glomerular filtration
- Tubular reabsorption ,99% , blood
- Tubular secretion , toxins
Filtration:
Filtration occurs in the renal Cor? across the filtration membrane
Fenestrated ca? = very l?
Pedicels of p? required to prevent larger sol? leaving the blood
Corpuscle
Capillaries
Leaky
Podocyte , solutes
Filtration:
Fluid filtered / day Males = 1?0 l/ day Females = 1?0 l/ day 9?% reabsorbed into bloodstream 1-? L urine/ day
180
150
99%
2
Regulation of filtration rate
Glomerular filtration rate (—) = amount of filtrate produced by the kidneys every ?
Maintained at 12? ml/min
Kidneys regulate the vascular tone of the Afferent and efferent art? to maintain correct filtration pressure
GFR
Minute
125
Arterioles
Tubular reabsorption and secretion :
Tubular reabsorption returns 9?% of w? and filtered sol? back to the bloodstream.
Reabsorption can be passive or a? >= A?P
Concentration ? allow diffusion of solutes
Os? gradients allow diffusion of water molecules
Solutes too big are secreted out of blood
99% Water, solutes Active , ATP Gradients Osmotic
Renal tubules
There are ? Renal tubules
They are
Proximal convoluted tubule = epithelial cells with micro villi. Most ab? done here.
Nephron loop / loop Henle = divided into descending and a? limbs
Distal convoluted tubule = cells lack micro villi
3
Absorption
Ascending
Proximal convoluted tubule
6? % water, N-+ , K+ reabsorbed
100% of gl? and a? a?
65, Na+
Glucose , amino acids
Nephron loop/ loop Henle
Tube loops down into m?
20% water reabsorbed
Descending limb = ?
Ascending limb = mostly solutes –+ ? and Cl-
Medulla
Water
Na+