Urinary

Question 1

Urinary System includes

Answer 1

kidney
urinary bladder
two ureters
urethra

Question 2

kidney function

Answer 2

the cleansing

remove wastes, toxins, excess toxins
reabsorb water, excretory
reg volume and chem comp

Question 3

Kidney external layers

Answer 3

Renal capsule: fibrous sheath
Adipose capsule: fatty protection
Renal fascia: connective

Question 4

3 internal layers of kidneys

Answer 4

Renal cortex: has glomerus
Medulla: pyramids. collect urine
Pelvis: funnel to ureter

Question 5

Nephron basic info

Answer 5

functional unit
1,000,000+!!!
LOTS of SA

Question 6

Proximal Tubule? (PCT)

Answer 6

reabsorption and secretion.
cuboidal w microvilli

Question 7

loop of Henle

Answer 7

Na+ and water reclamation.
Descending = thin = squamous: water perm
Ascending=thick=cuboidal, water imperm

Question 8

Distal tubule (DCT)

Answer 8

secretion and reabsorption, but less than PCT
squamous (thin), few microvilli

Question 9

Cap bed of Nephron

Answer 9

glamerous, peritubular cap, juxtaglam

Question 10

Glamerous BP

Answer 10

higher (50mmHG)
normal (35-18)

High BP forces fluids out of fenestrations

Question 11

Filtration apparatus

Answer 11

podocyte foot process
basement membrane
fenestrations inside bowman’s capsule

Question 12

Peritubular cap

Answer 12

branches of efferent
intimate w renal tubules
low P, porous = absorb!!
vasa recta is the deep stuff

Question 13

Juxtaglamerous apparatus

Answer 13

DCT curves back to efferent/afferent at beginning

Question 14

3 juxtaglamerous cells

Answer 14

Juxta cells (JG): responds to low stretch/BP by releasing Renin. By Junction

Macula Densa: osmolarity sensitive. Low flow = vasodilation. High flow = constrict

mesangial: contractile surrounding glamerous cap. can inc or dec glam SA to control filter rate

Question 15

How much do kidneys process?

Answer 15

180L/47 gal
1.8L leaves body = 1%

Question 16

what molecules pass freely?

Answer 16

less than about 8nM (water, glucose, amino acids, urea, salts)

Question 17

molecules that can’t pass thru?

Answer 17

Larger molecules (proteins/albumin, RBCs, WBCs)

Question 18

Glam filter rate (GFR) influenced by 3 factors:

Answer 18

1. total SA
2. perm of filters
3. P within glam (Net filt P: NFP)

*too much filt overwhelms = loss of water and ions
*too little = absorb everything, inc waste = useless

Question 19

Intrinsic control of GFR

Answer 19

self reg BP by Tubuloglam mech: mascula densa resp to high/low flow and osmolarity by constrict/dilate

Question 20

Extrinsic control of GFR

Answer 20

reg total BV and BP
Renin stim by reduced stretch by JG (activated by mascula densa, symp neurons)

Question 21

Tubular reabsorption

Answer 21

ATPase drives
Reabsorption of water, Na+, amino acids, fatty acids, glucose, minerals from filtrate, through epithelial cells of renal tubule, through
interstitial space, into peritubular cap. Most
tubular reabsorption occurs in PCT.

Question 22

tubular secretion

Answer 22

get those big suckers out

Question 23

ANP

Answer 23

released in response to high blood pressure (stretch of atria). Acts to reduce blood
pressure by…

relaxing mesangial cells to increase GFR, inhibits renin/angiotensin system, and causes dilation of afferent arterioles.

Question 24

ADH

Answer 24

released in response to low blood pressure.
o Controls expression of aquaporins in collecting duct.

Question 25

Aldosterone

Answer 25

released in response to low blood pressure. Increases blood pressure by increasing tubular reabsorption through control of the number of Na+/K+ ATPases in PCT and DCT.

Question 26

Polycystic kidney disease:

Answer 26

primary cilia deficiency. Primary cilia are sensory organelles that often sense fluid flow in various ducts and blood vessels. PKD affects 1 in 500 – 1000 people and usually manifests in 3rd decade of life. o Eventually leads to organ failure

Question 27

Kidney stones.

Answer 27

In general, stones form when there are imbalances of components in the urine that either promote or inhibit formation of the stone. Most stones are made of calcium that precipitates in the kidney.

Question 28

Glomerular nephritis:

Answer 28

Inflammation of the glomerulus. Most GM happens after an infection when antibodies precipitate on glomerular filtration membrane and activate complement system. This causes inflammation on the glomerulus, increased permeability, and decreased function. RBC and WBCs can be found in urine.

Question 29

Kidney failure:

Answer 29

Most common causes are diabetes and high blood pressure. o Hypertension contributes to atherosclerosis and damage to all blood vessels including renal and other arteries leading up to the glomerulus. Reduced blood flow decreases renal function. o Diabetes contributes to renal failure because high levels of glucose progressively damages nephrons. o The only treatment for kidney failure is dialysis or kidney transplant.