lecture 29

Question 1

which kidney is most inferior and why?

Answer 1

The right kidney is a little bit lower because it sits below the liver

Question 2

Which structures comprise a kidney lobe?

Answer 2

one medullary pyramid and all the cortex that surrounds it

Question 3

what is the nephron?

Answer 3

microscopic functional unit of the kidney responsible for urine formation

Question 4

How many nephrons are their per kidney?

Answer 4

~1 million per kidney

Question 5

How many types of nephrons are there?

Answer 5

two different types

Question 6

what are the two types of nephrons?

Answer 6

Cortical nephrons

juxtamedullary nephrons

Question 7

what is the most common type of nephron?

Answer 7

cortical nephrons ~85%

Question 8

where are cortical and juxtamedullary nephrons located?

Answer 8

cortical nephrons lie mainly in the cortex

juxtamedullary nephrons extend deep into the medulla

Question 9

what are juxtamedullary nephrons important for?

Answer 9

formation of concentrated urine

Question 10

Functions of nephrons?

Answer 10

selectively filter blood
return to blood anything to be kept
carry waste away for storage and expulsion

Question 11

Each nephron is comprised of?

Answer 11

a glomerular capsule
renal tubules
a collecting duct

Question 12

Each nephron is associated with?

Answer 12

a glomerulus

peritubular capillaries

Question 13

Glomerular capillaries are specialised for?

Answer 13

filtration

Question 14

what type of capillaries are glomerular capillaries?

Answer 14

thin walled single layer of fenestrated endothelial cells

Question 15

how are glomerular capillaries fed and drained?

Answer 15

By arterioles

Question 16

peritubular capillaries are specialised for?

Answer 16

absorption

Question 17

Peritubular capillaries wrap around what?

Answer 17

renal tubules

Question 18

peritubular capillaries receives what?

Answer 18

filtered blood from glomerulus via efferent arterioles

reabsorbed filtrate from nephron

Question 19

what are the vasa recta?

Answer 19

extensions that follow loops of Henle deep into the medulla

Question 20

Vasa recta are only found where?

Answer 20

with juxtamedullary nephrons

Question 21

Glomerulus is enclosed by?

Answer 21

glomerular capsule to form renal corpuscle

Question 22

the renal corpuscle is where what meets?

Answer 22

capillary and nephron meet

Question 23

the renal corpuscle is the site of what?

Answer 23

filtration barrier

Question 24

What is the first part of the nephron?

Answer 24

glomerular capsule

Question 25

What are the two layers of the glomerular capsule?

Answer 25

Outer parietal layer of simple squamous cells | inner visceral layer of podocytes

Question 26

Between the two layers of the glomerular capsule is?

Answer 26

Capsular space which receives filtrate

Question 27

what are podocytes surrounded by?

Answer 27

glomerular capillaries

Question 28

what are podocytes?

Answer 28

very branched, very specialised epithelium

Question 29

what are pedicels?

Answer 29

branches from intertwining foot processes of podocytes

Question 30

What forms between pedicels?

Answer 30

filtration slits

Question 31

what passes through filtration slits?

Answer 31

filtered blood passes through and into the capsular space

Question 32

what are other names for filtration barrier?

Answer 32

blood-urine barrier | glomerular capsular membrane

Question 33

where does the filtration barrier lie?

Answer 33

between blood and capsular space

Question 34

what is allowed to pass filtration barrier?

Answer 34

water and small molecules

Question 35

what is restricted by filtration barrier?

Answer 35

most proteins and red blood cells

Question 36

what are the three layers of the filtration barrier?

Answer 36

fenestrated endothelium of glomerular capillary fused basement membrane filtration slits between the pedicels of the podocytes

Question 37

which structures form renal corpuscle?

Answer 37

glomerulus | glomerular capsule

Question 38

what happens after flirtation?

Answer 38

waste fluid and solutes filtered from the blood, some of which is reabsorbed and a lot further screened

Question 39

what does urine =?

Answer 39

filtered - (reabsorbed + secreted)

Question 40

What is the role of the proximal convoluted tubule?

Answer 40

bulk reabsorption

Question 41

what surrounds the proximal convoluted tubule?

Answer 41

peritubular capillaries

Question 42

What epithelium is the proximal convoluted tubule?

Answer 42

cuboidal epithelial cells

Question 43

what structure reflects the function of the PCT?

Answer 43

dense microvilli on luminal membrane and highly folded basolateral membrane

Question 44

What is the purpose of mitochondria in PCT?

Answer 44

to provide energy for bulk active transport of molecules like glucose

Question 45

where does the nephron loop extend to?

Answer 45

from PCT and down into the medulla

Question 46

Why is length important for nephron loop?

Answer 46

for production of dilute/concentrated urine

Question 47

what surrounds the nephron loop?

Answer 47

vasa recta, in juxtamedullary nephrons only

Question 48

what forms the thick descending limb of nephron loop?

Answer 48

cuboidal epithelium cells, similar to PCT

Question 49

what epithelium are the thin limbs of the nephron loop?

Answer 49

simple squamous epithelium

Question 50

what forms the distal convoluted tubule?

Answer 50

cuboidal epithelium, thinner than PCT

Question 51

what is the role of the DCT?

Answer 51

fine tuning, regulated reabsorption

Question 52

structure of the DCT?

Answer 52

few microvilli and no brush border | less mitochondria

Question 53

What influences reabsorption in DCT?

Answer 53

aldosterone

Question 54

What is the role of the collecting duct?

Answer 54

to collect filtrate from several DCTs which empty into the papilla

Question 55

what influences reabsorption in collecting duct?

Answer 55

ADH and aldosterone

Question 56

Structure of collecting duct?

Answer 56

wall of simple cuboidal epithelium principal cells for reabsorption intercalated cells for acid/base balance

Question 57

how do you distinguish between proximal and distal convoluted tubule?

Answer 57

proximal has a fuzzy lumen due to microvilli and distal has a clear lumen

Question 58

what is the juxtaglomerular apparatus?

Answer 58

specialised zone in every nephron located where DCT lies against afferent arteriole

Question 59

What is the role of the macula dense cells?

Answer 59

chemoreceptors detect sodium levels

Question 60

what is the role of the juxtaglomerular cells?

Answer 60

mechanoreceptors detect blood pressure

Question 61

what does juxtaglomerular apparatus control?

Answer 61

glomerular filtration rate and blood pressure