Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Renal > Physiology > Flashcards

Physiology Flashcards

1
Q

define osmolarity

A

concentration of osmotically active particles in a solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

define osmolality

A

this is interchangeable with osmolarity for body fluids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

osmolarity of body fluids?

A

300mosmol/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

define tonicity

A

effect a solution has on cell volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

define isotonic

A

no change on cell volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

define hypertonic

A

decreases cell volume, concentrated salt solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

define hypotonic

A

increases cell volume (lysis) due to dilute solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what does tonicity also take into consideration?

A

ability of a solute to cross the cell membrane e.g. urea causes RBC lysis as water follows (sucrose is impermeable so has no effect)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

two compartments of total body water

A

intracellular fluid

extracellular fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what does the extracellular fluid consist of?

A

plasma

interstitial fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

tracer used to measure TBW

A

3H2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

tracer used to measure ECF

A

inulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

tracer used to measure plasma

A

labelled albumin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

inputs in water homeostasis

A

fluid
food
metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

outputs of water homeostasis

A 
insensible losses (no sensible mechanism- skin and lungs)
sensible losses- sweat, faeces and urine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what separates plasma and interstitial fluid?

A

capillary wall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what separates interstitial fluid and intracellular fluid?

A

plasma membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

main ions in ECF

A

Na+
Cl-
HCO3-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

main ions in ICF

A

K+
Mg2+
-ve charged proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

define fluid shift

A

movement of water between ICF and ECF in response to an osmotic gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

is Na+ excluded from ICF?

A

yes so there is only water movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what do the kidneys do to ECF

A

alter composition and volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

why is potassium balance important?

A

membrane potential (if leakages or increased uptake it can cause paralysis and cardiac irregularities)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

why is sodium balance important

A

ECF concentration and volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

kidney functions

A 
water balance
salt balance
maintenance of plasma volume
acid-base balance
excretion of waste
secretion of renin, erythopoietin and conversion of vit D
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

two types of nephron

A

juxtamedullary (glomerulus near corticomedullary border)

cortical (glomerulus in outer cortex)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

glomerular filtration barriers

A
  • endothelium (barrier to RBC)
  • basement membrane (basal lamina)
  • slit processes of podocytes (glomerular epithelium)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

define glomerular filtration rate (GFR)

A

rate protein-free plasma is filtered from the glomeruli into Bowman’s capsule per unit time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is normal GFR?

A

125ml/min

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

extrinsic regulation of GFR

A

sympathetic control via baroreceptor reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

intrinsic regulation of GFR

A

myogenic mechanism and tubuloglomerular feedback

32
Q

define tubuloglomerular feedback

A

GFR rises then more NaCl flows through the tubule causing constriction of afferent arteriole

33
Q

what senses NaCl concentration in the blood?

A

macula densa of DCT

34
Q

calculi effect on GFR?

A

reduced

35
Q

diarrhoea effect on GFR

A

reduced

36
Q

burns effect on GFR

A

increases

37
Q

example of a substance with clearance of 0 (completely reabsorbed)

A

glucose

38
Q

example of substance that is partly reabsorbed (clearance < GFR)

A

urea

39
Q

example of substance that is completely secreted (clearance > GFR)

A

H+

40
Q

what marker can be used to measure renal plasma flow

A

para-amino hippuric acid (PAH)- exogenous organic anion

41
Q

normal renal plasma flow

A

650ml/min

42
Q

what happens to PAH

A

it is all secreted from peritubular capillaries

43
Q

define filtration fraction

A

fraction of plasma flowing through the glomeruli that is filtered into the tubules

44
Q

what does the PCT reabsorb?

A 
sugars
amino acids
phosphate
sulphate
lactate
45
Q

what does the PCT secrete?

A 
H+
hippurates
neurotransmitters
bile pigments
uric acids
drugs
toxins
46
Q

what channel is used in the PCT for Na+ reabsorption?

A

Na+/K+ ATPase

47
Q

define transport maximum (Tm)

A

point at which increases in concentration of a substance do not result in an increase in movement of a substance across a cell membrane

48
Q

where is all glucose and amino acids reabsorbed in the nephron?

A

PCT

49
Q

what is normal concentration of glucose entering filtrate and whats renal threshold

A

2mmol/min

10-12mmol/L (consider diabetes)

50
Q

define the counter-current multiplier

A

loop of Henle creates a solute gradient allowing formation of hypertonic urine

51
Q

descending limb role of the nephron

A

does not reabsorb NaCl but is permeable to water

52
Q

role of the ascending limb of the nephron

A

Na+ and Cl- are reabsorbed (thick limb is AT and thin limb it is passive)
impermeable to water

53
Q

what cycle also contributes to medullary osmolality?

A

urea cycle

54
Q

is the DCT permeable to urea?

A

no

55
Q

which part of the nephron absorbs urea

A

collecting duct

56
Q

where does urea diffuse passively into?

A

loop of Henle

57
Q

what is the counter-current exchanger?

A

vasa recta

58
Q

what does the blood do in the vasa recta?

A

equilibrates with interstitial fluid

59
Q

why are the vasa recta needed?

A

they provide nutrients for medulla and remove toxins but to minimise removal of needed NaCl and urea for the concentration gradient they have low blood flow and are freely permeable so passive exchange preserves gradient

60
Q

what hormones influence DCT and collecting ducts?

A

ADH
aldosterone
ANH/P
PTH

61
Q

two segments of DCT

A 
early= Na+/K+/2Cl- transporter
late= aldosterone
62
Q

define ADH

A

octapeptide that is synthesised in the hypothalamus and stored in the posterior pituitary

63
Q

role of ADH

A

increases the number of aquaporins

64
Q

most important stimulus for ADH release?

A

hypothalamic osmoreceptors

65
Q

what secreted aldosterone?

A

adrenal cortex

66
Q

why is aldosterone secreted

A

increased K+ or reduced Na+

activation of RAAS

67
Q

role of aldosterone

A

stimulates Na+ reabsorption and K+ secretion

68
Q

what happens in the DCT when aldosterone is absent

A

rest of K+ is reabsorbed so there is none in the urine

69
Q

what is renin released from?

A

granular cells in the JGA

70
Q

processes that cause renin release

A
  • reduced pressure in afferent arteriole
  • low NaCl sensed by macula densa
  • increased sympathetic activity in low BP
71
Q

what produces atrial natriuretic peptides?

A

atrial cells

72
Q

what causes ANP release?

A

atria stretching due to increased blood volume

73
Q

role of ANP

A

promotes excretion of Na+ and diuresis

74
Q

define water diuresis

A

increased urine flow but not increased solute excretion

75
Q

define osmotic diuresis

A

increased urine flow as a result of increased salt excretion

Renal (54 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions