Renal function

Question 1

What are the physiological functions of the kidneys

Answer 1

regulate extracellular fluid solute concentrations
regulate plasma electrolye concentrations
regulate acid-base balance
regulate extracellular fluid volume, arterial blood pressure
eliminate metabolic wastes, foreign chemicals

Question 2

What hormones do kidneys produce

Answer 2

erythropoietin, vit D and renin

Question 3

what compunds are synthesized in kidneys

Answer 3

ammonia, PGs, kinins and glucose

Question 4

What other body systems are the kidneys intergrated with

Answer 4

GI, endo, CNS, ANS, CNS, resp, CV, liver

Question 5

what are some of the key sequlae to kidney failure

Answer 5

anemia due to loss of forming new RBC
osteoporosis due to loss of forming bone
disregulation of Ca and phosphates

Question 6

what is another name for interlobular aa

Answer 6

cortical radial arteries

Question 7

what portion of CO does the renal blood receive

Answer 7

20%

Question 8

are the glomerular capiilaries high or low P and why?

Answer 8

high pressure to cause filtration of blood

Question 9

are the peritubular capillaries high or low P and why?

Answer 9

low because want to reabsorb

Question 10

how are the P in the capillaries altered in renal system

Answer 10

changes in afferent and efferent arteriolar resistance

Question 11

What are the two types of nephrons

Answer 11

Juxtamedullary which go deeper to renal papilla

Superficial cortical

Question 12

characteristics of superficial cortical nephrons

Answer 12

short loops of henle

surrounded by particular capillaries

Question 13

characteristics of juxtamedullary nephrons

Answer 13

long loops of henle
efferent arterioles are covered by vasa recta (specialized peritubular capillaries)
mainly functions for urine concentration

Question 14

describe the renal microcirculation path

Answer 14

afferent arteriole
glomerular capillaries
efferent arteriole
peritubular capillaries

Question 15

describe venouse drainage of nephrons

Answer 15

interlobular v
arcuate v
interlobar v
renal v

Question 16

what are the advantages of high renal blood flow

Answer 16

high filtration rate

Question 17

how does renal fraction change during exercise

Answer 17

it decreases because shunting to skel muscle and want to retain H2O

Question 18

What regions of the kidneys receive more blood

Answer 18

the cortical nephrons

Question 19

how does blood perfusionc hang with aging

Answer 19

decreases because we lose the number of functioning nephrons

Question 20

where do sympathtetic neurons synapse in kidneys

Answer 20

smooth muscle to cause arteriolar constriction to protect from high BP
granular cells to cause renin secretion in afferent arterioles

Question 21

what is the function of renin

Answer 21

to cause retention of Na and H2O

Question 22

what are the net effects of sympathetic stimulation

Answer 22

decrease renal blood flow and diver renal fraction to vital organs

Question 23

what is glomerular filtration

Answer 23

filtration of plasma from glomerular capillaries into Bowmans capsule

Question 24

what is tubular reabsorption

Answer 24

transferal of substances from tubular lumen to pertibular capillaries

Question 25

what is tubular secretion

Answer 25

trasnferal of substances from peritubular capillaries to tubular lumen, like waste such as urea

Question 26

what is excretion

Answer 26

voiding substances in the urine

Question 27

how can we calculate urinary excretion

Answer 27

amount filtered-amount reabsorbed+amount secreted

Question 28

how can we measure tubular reabsorption

Answer 28

glomerular filtration- urinary excretion

Question 29

what is glomerular filtration rate

Answer 29

volume of plasma filtered per unit time

Question 30

the filtration rate of a substance is calculated how

Answer 30

GFR x plasma concetration of substance

Question 31

how do we calculate urinary excretion rate

Answer 31

product of urine flow rate x concentration of substance in the urine

Question 32

if excretion is less than filtration what does that indicate | if excretion is more than filtration what does that indicate

Answer 32

when excretion filtration- net secretion occurred

Question 33

what is the definition of clearance

Answer 33

the volume of plasma from which a substance is completely removed by kidneys in a given time period

Question 34

what are the units of clearance

Answer 34

volume/time ml/min L/hr

Question 35

Is clearance the same for all substances

Answer 35

no

Question 36

how do we calculate clearance

Answer 36

concentration of X in urine * urine volume ___________________________________ concentration of x in plasma

Question 37

Under what conditions can GFR be estimated from clearance

Answer 37

compound can freely filter thorugh glomerulus, cannot be secreted, reabsorbed, produced nor degraded by kidneys

Question 38

What molecules do we use to calculate GFR

Answer 38

inulin because it is not secreted reabsorbed or metabolized | Creatinine- not perfect and used for long term

Question 39

describe how the BUN creatinine ration works

Answer 39

because creatinine is unaffected by hydration status it acts as a constant. so we can tell when urea is too high or low.. where the problem may be in kidney problems Cystatin C

Question 40

describe what a BUN/C ratio above 20 indicates

Answer 40

prerenal problem BUN reabsorption is increased reduced perfusion due to hypovolemia

Question 41

What is a normal BUN/C level

Answer 41

10-20/1

Question 42

what does a BUN/C ratio below 10 suggest

Answer 42

intrarenal problem | renal damage causing reduced reabsorption of BUN

Question 43

what are the advantages of using Cystatin C to measure GFR rather than creatinine

Answer 43

no affected by muscle mass, age or gender

Question 44

What measurement of clearance can give an estimate of renal plasma flow

Answer 44

Para-amino hippuric acid

Question 45

What is the filtration fraction

Answer 45

part of renal plasma flow that is filtered/diverted into tubule

Question 46

what is the calculation for filtration fraction

Answer 46

FF= GFR/RPF

Question 47

the kidney is the only place that can rid the body of what acids

Answer 47

sulfuric acid and phosphoric acid

Question 48

what stimulates the kidneys to secrete erythropoeitin

Answer 48

hypoxia

Question 49

where is the macula densa

Answer 49

at the end of the ascending limb

Question 50

what type of reflex is micturition

Answer 50

autonomic spinal cord reflex

Question 51

how can the trigone be distinguished by the rest of the bladder

Answer 51

its mucosa is smooth unlike the extensive foldings of the rest of the bladder

Question 52

which sphincter of the bladder is voluntary

Answer 52

the external

Question 53

what spinal cords innervate bladder

Answer 53

S2S3 through sacral plexus, sensory and motor

Question 54

what type of fibers innervate detrusor mm

Answer 54

PANS

Question 55

what nerves innervate the external sphincter

Answer 55

skel mm nerves, pudendal | L2 also but not much

Question 56

a person with vesicoureteral reflex suffers the condition because

Answer 56

their ureters don't quite protrude as far into the bladder so the ureter is not completely blocked when bladder contracts

Question 57

what does the ureterorenal reflex prevent

Answer 57

preventing excessive flow of fluid into a blocked ureter

Question 58

what substances usually are filtered but then completely reabsorbed

Answer 58

amino acids and glucose

Question 59

what substances are filtered in glomercular capillaries and completely secreted in peritubular capillaries

Answer 59

organic acids and bases

Question 60

what molecules in plasma do not get filtered

Answer 60

plasma Ca and plasma FA because are bound to protein