Kidneys

Question 1

A substance that is filtered into the renal tubules but is then fully reabsorbed:

inulin, glucose, para-aminohippurate (PAH)

Answer 1

glucose

Question 2

a substance that is filtered and secreted, so the entire amount of substrate is released in the first pass:

inulin, glucose, para-aminohippurate (PAH)

Answer 2

PAH

Question 3

a substance that is freely filtered and neither secreted or reabsorbed:

inulin, glucose, para-aminohippurate (PAH)

Answer 3

inulin

Question 4

inulin is a __ that is given by the mouth

Answer 4

starch

Question 5

inulin is freely filtered from the glomerular capillaries into Bowman’s capsule but it does not undergo

Answer 5

secretion or reabsorption in the kidney tubules

Question 6

the GFR can be calculated by the clearance of _ from plasma

inulin, glucose, para-aminohippurate (PAH)

Answer 6

inulin (since it is filtered by the kidneys but the kidneys don’t do anything to it, don’t secrete or reabsorb is)

Question 7

rate at which a substance is cleared from plasma =

Answer 7

volume completely cleared/time = urine concentration of the substance x urine volume/plasma concentration of the substrate

Question 8

if the clearance of a substance that is freely filtered is less than that of inulin then there is a net __

Answer 8

reabsorption of the substance

Question 9

if the clearance of a substance that is freely filtered is greater than that of inulin then there is a net __

Answer 9

secretion of the substance

Question 10

if the clearance of a substance that is freely filtered is equal to that of inulin then there is a net __

Answer 10

then neither secreted or absorbed OR it is both secreted and absorbed in equal amounts

Question 11

para-aminohippurate (PAH) is both

Answer 11

filtered and secreted

Question 12

para-aminohippurate (PAH) is used to estimate

Answer 12

renal plasma flow

Question 13

glucose and NaCl are filtered and

Answer 13

reabsorbed

Question 14

2 other things used to estimate the GFR besides inulin

Answer 14

BUN and serum creatinine

Question 15

the most accurate measure of GFR

Answer 15

serum creatinine

Question 16

___ and __ are what are used to assess if kidneys are functioning well. We produce urea and creatinine at constant rate. So if we excrete the same amount we make, the plasma concentration will remain constant. So if input = output = good. If creatine/Bun rises above normal = suggests kidneys dysfunction input doesn’t equal the output.

Answer 16

Creatinine and urea (bun)

Question 17

most of our nephrons are cortical nephrons or juxtamedullary nephrons

Answer 17

cortical (80%)

Question 18

which one concentrates and dilutes urine

cortical nephrons or juxtamedullary nephrons

Answer 18

juxtamedullary nephrons

Question 19

which one mainly performs excretory and regulatory functins

cortical nephrons or juxtamedullary nephrons

Answer 19

cortical nephrons

Question 20

what part of the nephron is under endocrine control

Answer 20

distal convoluted tubule

Question 21

PTH will make tubule reabsorb more _ and

Answer 21

reabsorb more calcium and excrete more phosphate

Question 22

Aldosterone will make

Answer 22

more sodium reabsorbed and more potassium excreted

Question 23

most secretion in the nephron occurs in what part

Answer 23

proximal tubule

Question 24

about _ of the total amount filtered is reabsorbed in the proximal tubule

Answer 24

2/3

Question 25

kidney secrete/reabsorb H+

Answer 25

secrete

Question 26

kidneys secrete/reabsorb bicarb

Answer 26

reabsorb

Question 27

phosphate compounds and ammonia act as

Answer 27

buffers

Question 28

phosphate ions are excreted along with

Answer 28

cations ex. Na+

Question 29

ammonium ions excreted along with

Answer 29

anions ex. Cl-

Question 30

ammonia is formed in _ cells by the deamination of certain amino acids, especially _

Answer 30

tubular | glutamic acid

Question 31

_ and _ provide good info on how much acid is being eliminated by the kidneys

Answer 31

phosphate and ammonium

Question 32

_ is the best overall index of kidney function

Answer 32

GFR = normally 120mL/minute

Question 33

clinically GFR is evaluated by measuring

Answer 33

plasma creatinine concentration

Question 34

GFR increases: 1. _ of afferent arterioles 2. _ of efferent arterioles 3. _ hydrostatic pressure in Bowman's capsule 4. _ plasma colloid pressure

Answer 34

1. vasodilation 2. vasoconstriction 3. decreased 4. decreased

Question 35

with inulin and creatinine the kidneys do not

Answer 35

reabsorb or secrete them

Question 36

If the kidneys do not reabsorb or secrete a substance, then the GFR =

Answer 36

clearance

Question 37

if the tubules reabsorb the substance, the clearance is _ than the GFR

Answer 37

less than

Question 38

if the tubules secrete the substance, the clearance is _ than the GFR

Answer 38

greater than

Question 39

if the tubules reabsorb AND secrete the substance, the clearance is _ than the GFR

Answer 39

less than, equal to, or greater than the GFR

Question 40

excessive constriction of the afferent arteriole will _ RBF and GFR

Answer 40

decrease

Question 41

the kidney dialysis machine resembles what part of the kidneys system?

Answer 41

countercurrent mechanical system

Question 42

the countercurrent multiplier in the medulla's loop of Henle is dependent on the _ reabsorption of NaCl by the thick ascending loop of Henle

Answer 42

active | thick

Question 43

countercurrent exchange occurs in the region of the peritubular capillary bed called the

Answer 43

vasa recta

Question 44

do the vasa recta create the medullary hyperosmolarity

Answer 44

no

Question 45

the vasa recta prevent the medullary hyperosmolarity from being

Answer 45

dissipated and can carry away water that has been reabsorbed

Question 46

reabsorption of glomerular filtrate would be most affected if modifications were made to the permeability of what section of the nephron

Answer 46

proximal convoluted tubule | bc 2/3 of the glomerular filtrate is reabsorbed in the proximal convoluted tubule

Question 47

almost 100% of the filtered glucose and amino acids are reabsorbed in the

Answer 47

proximal convoluted tubule

Question 48

the filtrate that enters into the proximal tubule from the capillaries are free of

Answer 48

large proteins

Question 49

Excretion rate =

Answer 49

filtrate + secretion - reabsorption

Question 50

how much filtrate does the body make per day

Answer 50

150-250L

Question 51

how much of the filtrate is excreted per day

Answer 51

1-2L of urine per day

Question 52

about _% of filtrate is returned to vascular system and _% is excreted as urine

Answer 52

99% | 1%

Question 53

the most important source of ammonia quantitatively is

Answer 53

amino acids

Question 54

what compound is converted to ammonia in the kidney

Answer 54

glutamine

Question 55

from amino acids many tissues but particularly the __ form ammonia by amino transferase and glutamate dehydrogenase reactions

Answer 55

liver

Question 56

from glutamine, the __ form ammonia by the action of renal glutaminase

Answer 56

kidneys

Question 57

amines obtained from diet and monamines that serve as hormones or NT give rise to ammonia by the action of

Answer 57

amino oxidase

Question 58

from purines and pyrimidines amino groups attached to the rings are released as

Answer 58

ammonia

Question 59

urea travels from _ to _

Answer 59

liver to kidneys

Question 60

___ directly catalyzes urea formation in a cell

Answer 60

arginase

Question 61

which of the following processes is not involved in the formation of urine filtration/reabsorption/excretion/secretion

Answer 61

excretion

Question 62

which 2 involve the most similar amounts of fluid transport | filtration/reabsorption/excretion/secretion

Answer 62

filtration and reabsorption | 99% of filtered is reabsorbed

Question 63

which work in the same direction | filtration/reabsorption/excretion/secretion

Answer 63

filtration and reabsorption

Question 64

filtration/reabsorption/excretion/secretion which is affected by ADH

Answer 64

reabsorption

Question 65

what cannot be filtered

Answer 65

formed elements = cells | and plasma proteins = too large

Question 66

normal urine is 1. clear/cloudy 2. _ color 3. acidic/basic 4. odor of

Answer 66

clear straw colored and slightly acidic and has odor of urea

Question 67

diuresis results from a decrease in tubular

Answer 67

reabsorption of water

Question 68

2 causes of dilute urine

Answer 68

absence of ADH | diabetes insipidus

Question 69

possible causes of concentrated urine

Answer 69

decreased plasma volume cellular dehydration DM excess ADH

Question 70

is a condition characterized by excessive thirst and excretion of large amounts of severely diluted urine, with reduction of fluid intake having no effect on the concentration of the urine

Answer 70

Diabetes insipidus (DI)