Functional histology of the kidney

Question 1

what components of the kidney nephron are in the cortex

Answer 1

bowmans capsule, glomerulus, pct, dct, collecting tubule

Question 2

what components of the kidney nephron are in the outer medulla

Answer 2

loop of henle- thick arm(ascending), collectimg duct

Question 3

what components of the kidney nephron are in the inner medulla

Answer 3

loop of Henle- thin arm( descending and ascending)

Question 4

briefly explain the three stages of glomerular filtration

Answer 4

materials pass through the fenestration between capillary endothelial cell of glomerulus which are about 50-100nm

then through the basement membrane of capillaery endothelial cells and podocytes

then through the filtration slit membrane between podocyte foot processes( 4nm pores)

Question 5

Describe pct cells

Answer 5

cuboidal in shape, many microvilli to increase surface area for reabsorption, pinocytotic vessicles to move macromolecules to the lysosimes, lysosomes to recycle macrmolecules, many mitochondria to fuel active transport with the na/k atpase
they have tight junctions between them to prevent the leakage of substances between them

Question 6

describe thin loop of Henle cells

Answer 6

they undergo reabsorption by passive flux only
they have thin squamous epithelial cells to allow passive fluxes
they have a minimum of organelles
the thin ascending loop of henle is permeable to water

Question 7

describe the thick loop of Henle and dct cells

Answer 7

they undergo regulated active transport and ion exchange
they have cuboidal epithelial cells whuch are thicker than squamous cellsto reduce passive flux and accomodate organells
many mitochondria to fuel active transport
few short mocrovilli unlike pct cells

Question 8

describe cells of the collecting tubule and CD

Answer 8

They undergo passive reabsorption of water
they have cuboidal to columnal eputhelial cells to regulate unregulated passive flux of water
dense membranes at cell contact

Question 9

describe the juxtaglomerlar apparatus

Answer 9

this is where the dct loops back to meet the efferent arteriole of the same nephron. there are three special cells there; the macula ensa, the juxtaglomerlar cells and the lacis cells

Question 10

describe function of macula densa

Answer 10

senses a change in the sodium level in the dct fluid and sends a signal to the juxtaglomerular(JG) cells

Question 11

describe fvunction of JG cells

Answer 11

they release renin inresponse to signal fdrom macula densa. renin indirectly increases vascular tone and sodium reabsorption

Question 12

describe the transverse section of the ureter