Kidney Anatomy

Question 1

Describe the external anatomy of the Kidney

Answer 1

1. right kidney is lower then the left due to liver crowding
2. renal hilum leads to renal sinus
   
   • ureters, renal blood vessels, lymphatics, and nerves enter/exit at hilum

Question 2

Layers of tissue supporting kidney

Answer 2

1. renal capsule- fibrous capsule that prevents kidney infection
2. adipose capsule- fatty mass that cushions and helps attach kidney to body wall
3. renal fascia- outer layer of dense fibrous connective tissue that anchors the kidney

Question 3

Kidneys internal anatomy

Answer 3

cortex, medulla, renal pelvis, major calyces, minor calyces

Question 4

kidneys blood supply

Answer 4

-1/4TH(1200ml) of systemic cardiac output flow through the kidneys each min

Question 5

Nephrons consist of:

Answer 5

• glomerulus:a tuft of capillaries associated with renal tubule
• renal tubules: made of glomerular capsule, proximal and distal convoluted tubes, and loop of henle

Question 6

anatomy of renal corpusle

Answer 6

1. renal corpuscle- the glomerulus and its bowmans capsule
2. glomerular endothelium- fenestrated epithelium that allows filtrate to pass from the blood into G.C.
3. G(bowmans) C- blind, cupshaped end of renal tubule that completely surrounds the glomerulus

Question 7

Renal tubule

Answer 7

1. proximal convoluted tubule- composed of cuboidal cells with numerous microvilli and mitochondria, reabsorbs water and solutes from filtrate and secretes substances into it
2. loop of henle- proximal part, then followed by thin segment(simple squamous) and then thick segment(cuboidal to columnar)
3. distal convoluted tubule- cuboidal cells without microvilli that function mostly in secretion

Question 8

connecting tubules

Answer 8

1. intercalated cells=
   a. cuboidal cells with microvilli
   b. function in maintaining pH
2. principal cells=
   a. cuboidal without microvilli
   b. help maintain bodys water/salt balance

Question 9

Nephron types

Answer 9

A.Cortical nephrons-85% of nephrons in cortex
B.Juxtamedullary nephrons: located in cortex-medulla junction, have extensive thin segments, involved in prod of concentrated urine

Question 10

Capillary beds of nephrons

Answer 10

Every nephron has two capillary bed:

1. Glomerulus:
   a. fed by an afferent arteriole
   b. drained by efferent art.
2. peritubular capillaries:
   a. low pressure, porous capillaries
3. Vasa recta: long, straight efferent arterioles of juxta medullary nephrons

Question 11

Juxtaglomerular Apparatus

Answer 11

1. where distal tubule lies against the afferent arterioule
2. arteriole walls have juxtaglomerular cells: enlarged smooth muscle cells, secretory granules containing renin, act as mechanoreceptors
3. macula densa: tall, closely packed distal tubule cells, lie adjacent to jg cells, function as chemoreceptors or osmoreceptors
4. Mesanglial cells: have phagocytic and contractile properties, influence capillary filtration

Question 12

Filtration Membrane

Answer 12

1. filter that lies between blood and interior of glomerular capsule
2. composed of three layers:
   a. fenestrated endothelium of glomerular capsule
   b. visceral membrane of glomerular capsule
   c. basement membrane composed of fused basal lamina of the other layers