Urinary System

Question 1

major functions of the urinary system

Answer 1

• removal of metabolic waste products from the blood: heme to bilirubn to urobilin (yellow)
• regulation of ion concentration (NA, K , etc)
• regulation of blood acid-base balance
• regulation of blood pressure (renin)
• regulation of RBC production (EPO)
• regulation of VitD production

Question 2

which hormones are synthesized and released by the kidney

Answer 2

-renin and EPO

Question 3

how does Vit D interat with the kidney

Answer 3

-synthesized in the skin but activated and released in the kidney

Question 4

role of vit D

Answer 4

• increases ca absorption in small intestine
• increases ca absorption in renal tubules
• increases osteoclast activity to increase ca levels

Question 5

renal artery branches into

Answer 5

-interlobar artery and then the arcuate artery and then the interlobular artery

Question 6

renal collumn is found where

Answer 6

in between renal pyramids

Question 7

renal pyramids dump into

Answer 7

renal pelvis

Question 8

lobules are seperated by

Answer 8

interlobular arteries

Question 9

renal corpuscle

Answer 9

-glomerulus and bormans capsule

Question 10

nephron

Answer 10

renal corpuslce and tubule

Question 11

uriniferous tubule

Answer 11

nephron and collecting duct

Question 12

cells found in the glomerulus

Answer 12

• endothelial cells
• mesangial cells
• podocytes

Question 13

glomerulus is surrounded by

Answer 13

-bowmans space and capsule

Question 14

how does the glomerulus and bowmans capsule facilitate filtration

Answer 14

-large afferent arterioles and small efferent arterioles

Question 15

mesangial cells

Answer 15

• support
• phagocytosis
• repair
• contractile
• BP monitoring (extraglomerular mesangial cels, lacis cells)

Question 16

podocytes

Answer 16

• surround the glomerulus and facilitate filtration by making small slits with long processes
• share a basement membrane with endothelial cells, filtrate passes through the spaces between the conjoining processes

Question 17

glomerular filtration

-composition of the filtration system

Answer 17

• 68,000MW allowed to pass through
• barrier is made with type 4 collagen network
• lamin network
• proteoglycans

Question 18

flow of blood that becomes filtrate in the kidney starting with the interlobar artery

Answer 18

• interlobary artery
• arcuate artery
• interlobular artery
• afferent arteriole
• into bowmans capsule
• proximal convoluted tubule
• loop of henle thick then thin
• distal convoluted tubule
• colecting duct

Question 19

job of the proximal and distal convoluted tubule

Answer 19

-to remove everything that is useful to us and leave veryting that isnt to be excreting

Question 20

where does the majority of resorbtion happen?

Answer 20

• 80% in the PCT

- PCT 3: 1 DCT

Question 21

characteristics of PCT

Answer 21

• brush border with enzyme rich glycocalyx
• endocytic vesicles
• basal infoldings
• abundant mitochondria
• Na/K ATPase

Question 22

characteristics of the DCT

Answer 22

• resorbs mostly water and Na
• no brush border
• fewer mitochondria
• aldosterone sensitive Na/K ATPase

Question 23

what is actively absorbed in the PCT

Answer 23

• Na (endocytosis)
• amino acids
• sugars
• peptides (endocytosis)

Question 24

passive absorption in the PCT

Answer 24

• water

- Cl

Question 25

two steps of resorption

Answer 25

- pump nutrients into the ECM | - uptake of nutrients into caps

Question 26

renal medulla

Answer 26

- generation of salt gradient - resorption of water - acid base balance

Question 27

what can we see in cross section of the kidney

Answer 27

- thin and thick loop of henle - vasa recta - collecting duct

Question 28

intercalated (dark) cells

Answer 28

- found in the collecting duct - regulate pH in the collecting duct - alpha cells release H+ - beta cells release HCO3-

Question 29

light cells

Answer 29

- found in the collecting duct - more common than the dark cells - respond to ADH and control water resorption - ciliated which serve as mechanosensors

Question 30

mutation in cilia of light cells in collecting duct

Answer 30

-mutation in polycystin-1,2 genes lead to ciliopathies and polycystic kidney disease

Question 31

what is the environment of the medulla like?

Answer 31

-salt-rich, allowing water to be resorbed through the collecting duct via osmotic pressure

Question 32

ADH

Answer 32

- generated by the pituitary (pons nervosa) - ats on the collecting duct to promote water resorption which concentrates the urine - this is blocked by booze which is why we pee so much

Question 33

diabetes | -insipidus and mellitus

Answer 33

- insipidus: inability to make or respond to ADH, you pee a lot - mellitus: insulin def leads to elevated glucose which leads to osmotic diuresis

Question 34

kidney stones

Answer 34

- crystals may form from calcium oxalate or uric acid precipitates - precipitation may be caused by low fluid intake, high protein diets, refined sugars - passage of stone is very painful - blockage may lead to hydronephrosis

Question 35

blood pressure monitoring

Answer 35

- arteial pressure in afferent arteriole are responded to by JG cells via baroreceptors - ion concentration in the DCT is responded to by macula densa (chemoreceptors)

Question 36

contents of the juxtaglomerular apparatus

Answer 36

- Jg cells - macula densa - lacis cells

Question 37

how do we increase BP?

Answer 37

- angiotensin is release by the liver and converted to angiotensin 1 via renin that is released from the kidney - angiotensin 1 is converted to angiotensin 2 via ACE - angiotensin 2 acts on the adrena cortex to release aldosteron which causes increased Na resorp in the DCt - angiotensin 2 also causes vasoconstriction and NaCl/H2O reabsorption in the kidney

Question 38

what type of epithelium is found on the surface of the minor calyx?

Answer 38

transitional aka urothelium | -this has the ability to stretch which causes the balloon cells to get thin on the surface

Question 39

ureter

Answer 39

- transitional epithelium - no muscularis mucosae - three layers in muscularis externa (distal portion only)