lecture 26-27 Flashcards
What is the role of bowman’s capsule?
It is the first step in the filtration of blood to form urine.
How dose bowman’s capsule work?
a bundle of capillaries called the glomerulas is wound within bowman’s capsule, which is very pours that allows ions to leave but not larger molecules like blood cells and platelets. These ions are then grabbed up by the bowmans capsule.
What is a nephron?
A structure found within the kidney (inner layer) that filter the blood.
True or false:
collecting ducts are connected to many nephrons
True
What is the next step after bowmans capsule?
The proximal tubule
What is the role of the proximal tubule?
The proximal tubule is covered in microvili to increase its surface area, allowing it to reabsorb Na+ and Cl- into them along with any other ions that are valuable.
What regulates Aquaporin?
ADH
What happens during periods of low ADH concentration?
You pee out more water.
What is are the layers of the kidney working from the outside in?
Cortex
Medulla
renal Pelvis
Ureter
Where is bowmans capsule located?
Within the cortex of the Kidney
Where is the loop of hendly found?
Within the Medulla
What is the relationship between Medulla thickness and urine concentration?
The thicker the medulla the more concentrated the urine.
Meaning that the loop of Henley must be involved in determining the concentration of urine
why would a desert animal need to have a super THICC loop of henley?
Becuase they want to hold onto water, the thicker the loop the more water is pulled out and the more concentrated the urine.
Would a bigger or smaller creature need to have a larger medulla?
A smaller creature. Large animals can more easily hold onto their water, thus they will have no need to invest evolutioon points into thicker Medullas within their kidneys.
True or false:
desert animals have larger loops of henley.
True,
How dose the loop of henley produce a single effect gradient?
through counter current multiplication
The descending limb is permeable where as the ascending limb is not permeable (although is actively transporting out (NaCl) into the interstitial fluid. Water then goes to balance this out from the descending tube.
This increases the concentration of the descending tube and of the interstitial fluid
Once it passes through the lop of henly, why don’t we always have super diluted urine.
This is because when we express aquaproin within the collecting duct (High ADH) then the water from the urine is absorbed back into the animals plasma (making the pee more concentrated)
or you express little aquaporin within the collecting duct (Low ADH) and water stays in the urine, allowing the animal to retain its ions among the urine more dilute.
Where is osmotic pressure the highest in the kidney?
It is highest within the medulla near the loop of Henley as salt is being actively pumped out into the medullas interstitial fluid.
Dose osmotic pressure within the medulla increase or decrease during dehydration?
It increases as you are actively attempting to hold onto water expressing high amounts of ADH to pull water back into the plasma of the animal.
How is water pulled out of the collecting duct?
Through a high concentration gradient created by the loop of Henley. This gradient pulls out water into the extracellular fluid from the collecting duct.
What is the Vasa Recta?
A mesh of capillaries found in the bowman’s capsule used in counter current exchange.
What can we expect to see in terms of development of the renal papilla in aquatic species, mesic species, and arid speices ?
aquatic: little or no development of renal papilla in freshwater species
mesic: there is some development of renal papilla
arid species: The renal papilla is highly developed as their loop of Henley is massive (holding onto as much water as possible by creating a massive salt gradient outside the collecting duct for water to be pulled out of)
What determines the size the of renal papilla?
The size of the loop of henle
True or false:
Rodents have slightly less organized kidneys
True
