Renal System Flashcards
What are the 4 major components of the renal system?
Kidney, Ureter, Bladder and Urethra.
What are the components of kidney structure?
Kidney cortex and renal medulla.
What are the functional units of kidneys?
Nephrons
How are nephrons categorised?
Into Renal Corpuscle (filtration) and Renal Tuble (reabsorption and secretion).
what are 80-85% of all nephrons called?
cortical nephrons
what are juxtamedullary nephrons?
long nephron loops surrounded by recta or straight vessels.
How is the renal corpuscle structured?
Glomerulus and Glomerular capsule or Bowman’s capsule.
What is the glomerulus capillary network?
Fenestrated capillaries; received blood from afferent arteriole.
What are Glomerular Capsules?
The inner visceral layer consisting of specialised cells called podocytes that cover the fenestrated capillaries.
Of the renal tube, how many main sections are there and what are they called?
There are 3. Proximal, Nephron and Distal.
What tubule has the greatest reabsorption capacity?
Proximal tubule
What do proximal tubule feature?
They have microvilli to increase surface area
How much of glucose and amino acids are reabsorbed here?
100%
What are thin ascending limb juxtamedullary nephrons constructed from?
Simple squamous cells
What are thick ascending limbs constructed from?
cuboidal or low columnar epithelium
What are the factors that drive net filtration?
Glomerular blood hydrostatic pressure, capsular hydrostatic pressure and blood colloid osmotic pressure
What arteriole has a smaller diameter?
Efferent arteriole
What does glomerular hydrostatic pressure do to fluid in capillaries?
Forces fluid out of glomerular capillaries.
What is GFR?
Glomerular filtration rate. How much blood our kidneys filter in total per minute.
What is the normal rate of GFR?
125ml per minute
What would be an end stage of renal failure GFR?
15ml or less.
How can we regulate GFR?
Renal autoregulation, neural and hormonal regulation.
What is Renal Autoregulation?
Regulates the blood entering the glomerulus
In relation to renal autoregulation, what are myogenic mechanisms.
They use the changes of vascular tone (constriction or contraction of vessels) to maintain desired blood flow.
In relation to renal autoregulation, what is tubuloglomerular feedback mechanism?
Uses alterations of the vasodilator nitric oxide
What receptors are present in the smooth muscle of afferent and efferent vessels?
Alpha 1
What does norepinephrine do to arteriole vessels?
Vasoconstrict
How can GFR be modulated (hormones)
ANP - atrial natriuretic peptide and Angiotensin II
What hormone will decrease GFR (glomerular filtration rate) ?
Angiotensin II
What hormone will increase GFR (glomerular filtration rate)?
ANP - atrial natriuretic peptide
What are the three different types of transporters in the renal tubule?
Active, Co-transport and antiporters.
What are the similarities and differences between co-transport and antiporter transport?
They both move 2 or more solutes in a certain direction of the renal tubule. However, they differ in that co-transport moves in the same direction and antiporter transport moves in opposite directions.
In the nephron loop of the loop of henle, where does osmolality increase?
The descending limb
In the nephron loop, where does osmolality decrease or reduce?
The ascending limb
In the distal tubule, what do principle cells reabsorb?
Na+ and K+
In the distal tubule, what do intercalated cells reabsorb and/or secrete.
Secretes H+ – Reabsorbs or Secretes HCO3 ions.
What division of the renal tubule achieves the most secretion?
The proximal tubule
