Lecture 6: Histology (Cortes-Hinojosa) Flashcards
Order pronephros, mesonephros, and metanephros in order of evolution
pronephros –> mesonephros –> metanephros
Name 3 things found in the medullary rays*****
1) Proximal straight tubules
2) Distal straight tubules
3) Cortical collecting ducts
Name 3 things found in the cortical labyrinth*****
1) glomeruli
2) proximal convoluted tubules
3) distal convoluted tubules
What structures are in the CORTEX?**
Medullary rays (PST, DST, CD) and cortical labyrinth (PCT, DCT, glomeruli)
What structures can be found in all regions of the MEDULLA?**
Collecting duct
Thin tubule
PST
What structures are in the outer stripe of the medulla?**
PST, DST, collecting duct
What structures are in the inner stripe of the medulla?**
DST, thin limb of loop of Henle, collecting duct
Thick ascending limb of loop of henle =**
distal straight tubule
Thick descending limb of loop of henle = **
proximal straight tubule
What structures are in the outer medulla (outer + inner stripes)?
PST, DST, thin limb of loop of Henle, collecting duct (PST and DST are thick limbs!)
PST and DST are considered thin or thick limbs?
thick
What is found in the inner medulla?
thin limbs and collecting duct only
Structures found in both cortex and at least one region of the medulla
Collecting duct
PCT
DCT
Pathway of blood in the kidney
renal a.–> lobar a. –> arcuate a. –> interlobular a. –> afferent arterioles –> glomerular capillaries –> efferent arterioles –> peritubular capillaries –> vasa recta (to medulla)
Where are arcuate aa. found?
at corticomedullary junction
What is the mesangium?
Inner layer of the glomerulus within the basement membrane surrounding the glomerular capillaries. The cells are phagocytic and secrete the amorphous mesangial matrix
What drives solute and water reabsorption in the proximal tubule?
basolateral plasma membrane infoldings containing Na/K ATPase
Main fxs of loop of Henle
- generation and maintenance of medullary interstitial gradient
- regulation of H2O balance and urea excretion
3 main nephron segments of loop of Henle
1) PST
2) Thin limbs (w/ hairpin turn)
3) Thick ascending limb (DST)
what kind of animal secretes urea?
mammals
what kind of animal secretes uric acid?
birds and reptiles.
T or F: reptiles and birds don’t have Loops of Henle
true
tubule fluid bypasses what in short-looped nephrons? Why is this important?
inner medulla. Enhances water excretion
Advantage of long-looped nephrons
Water reabsorption enhanced because countercurrent exchange maintains medullary gradient
