Physiology

Question 1

Osmolarity

Answer 1

Concentration of osmotically active particles in a solution

Question 2

Units of osmolarity

Answer 2

Osmol/L

Mosmol/L for body fluids

Question 3

2 known factors needed to calculate osmolarity

Answer 3

Molar concentration

No. of osmotically active particles

Question 4

tonicity

Answer 4

Affect solution has on a cell

Question 5

affect on cell in hypotonic solution

Answer 5

Solution has lower solute and higher water concentration than the cell
The cell gains water
Lysis (cell bursts)

Question 6

affect on cell in hypertonic solution

Answer 6

Solution has a higher solute concentration and lower water concentration than the cell
The cell loses water
Shrinks

Question 7

Affect of urea on RBCs

Answer 7

Urea is hypotonic

Cell lysis

Question 8

Compare ion composition of ECF + ICF

Answer 8

ECF high in Sodium + chlorine + bicarbonate

ICF high in potassium + magnesium

Question 9

how does 0.9% saline affect osmolarity and ECF volume

Answer 9

NO CHANGE in osmolarity

Changes ECF volume

Question 10

Tracer used for full body water

Answer 10

3H20

Question 11

Tracer used for ECF

Answer 11

Inulin

Question 12

Tracer used for plasma

Answer 12

Labelled albumin

Question 13

Which starling forces favour filtration

Answer 13

Capillary hydrostatic pressure (55mg)

Bowmans oncotic pressure (0mg)

Question 14

which starling forces oppose filtration

Answer 14

Capillary oncotic (30mg)
Bowmans hydrostatic (15mg)

Question 15

how does Diarrhoea affect GFR

Answer 15

Increases capillary oncotic pressure so decreases GFR

Question 16

How does a renal stone affect GFR

Answer 16

Increases bowman hydrostatic pressure so decrease GFR

Question 17

how does afferent arteriole dilation affect GFR

Answer 17

Increases GFR

Question 18

What causes afferent arteriole dilation

Answer 18

Prostaglandins

ANP

Question 19

Which drugs cause constriction of afferent arteriole

What is the effect on GFR

Answer 19

NSAIDS

decreased GFR

Question 20

Which drugs cause dilation of efferent arteriole

What is the effect on GFR

Answer 20

ACE/ARBS

decreased GFR

Question 21

How does efferent arteriole constriction affect GFR

Answer 21

Increased GFR

Question 22

What causes efferent arteriole constriction

Answer 22

ANP
Angiotensin 2
Norepinephrine

Question 23

clearance is greater than GFR

Answer 23

substance is secreted

Question 24

Clearance is less than GFR

Answer 24

substance is partially reabsorbed

Question 25

clearance of what substance = GFR

Answer 25

Inulin

Question 26

Why is glucose clearance 0

Answer 26

It is filtered and completely resorbed

Question 27

what is PAH

Answer 27

Marker used to calculate renal flow

Question 28

what needs to happen to a substance for it to be used as a marker of renal flow

Answer 28

needs to be completely secreted

Question 29

what needs to happen to a substance for it to be used as a marker for GFR

Answer 29

needs to be freely filtered and neither secreted nor reabsorbed

Question 30

what is filtration factor

Answer 30

Fraction of plasma flowing through the glomeruli that is filtered into tubules (20%)

Question 31

where does most of reabsorption happen

Answer 31

proximal tubule

Question 32

what is absorbed in descending limb of loop of henle

Answer 32

water

Question 33

what is absorbed in ascending limb of loop of henle

Answer 33

NaCl

Question 34

What does the loop of henle generate

Answer 34

cortico-Medullary concentration gradient

Question 35

primary active transport

Answer 35

energy directly required

Question 36

secondary active transport

Answer 36

substance transported coupled to concentration gradient of an ion (usually sodium)

Question 37

what do loop diuretics block

Answer 37

Na-K-Cl co transporter

Question 38

function of K+ recycling

Answer 38

Ensures NaCl is absorbed into interstitium

Question 39

Which tubule is not permeable to urea

Answer 39

Distal tubule

Question 40

Sodium resorption affects chlorine in what way

Answer 40

drives Cl resorption through paracellular pathways

Question 41

filtration equation

Answer 41

plasma concentration x GFR

Question 42

Resorption equation

Answer 42

Rate of filtration - rate of excretion

Question 43

Excretion equation

Answer 43

(filtration+ secretion) - resorption

Question 44

Secretion equation

Answer 44

Rate of excretion - rate of filtration

Question 45

Functional unit of kidney

Answer 45

Nephron

Question 46

Differences between the 2 types of nephron

Answer 46

Juxtamedullary- long loop of henle, has a vasa recta | Cortical- short loop of henle

Question 47

Which nephron concentrates urine

Answer 47

Juxtamedullary

Question 48

Which cells in juxtamedullary nephron secrete renin

Answer 48

Granular cells

Question 49

Which cells sense sodium concentration of distal convoluted tubule

Answer 49

macula densa

Question 50

Where is a fall in renal perfusion pressure detected

Answer 50

Baroreceptors in afferent arteriole

Question 51

Function of ADH

Answer 51

Increases water reabsorption

Question 52

Function of aldosterone

Answer 52

Increases Na absorption, increased K+ excretion

Question 53

Function of ANH

Answer 53

Decreases Na absorption

Question 54

Where is ANH produced + when is it released

Answer 54

Heart, stored in atrial muscle cells Released when atrial cells are stretched due to Increased circulating volume Causes increased sodium excretion therefore water is loss and plasma volume decreases

Question 55

High levels of ADH

Answer 55

High water permeability | Hypertonic urine i.e. small volume of concentrated urine

Question 56

Low levels of ADH

Answer 56

Low water permeability | Hypotonic urine i.e. large volume dilute urine

Question 57

affect of atrial pressure on ADH

Answer 57

Decreased atrial pressure increased ADH release

Question 58

Water diuresis

Answer 58

Increased urine flow but not an increase in solute excretion

Question 59

Where do loop diuretics act

Answer 59

Thick portion of ascending limb of henle

Question 60

where do thiazide diuretics act

Answer 60

Distal convoluted tubule

Question 61

Where does aldosterone act

Answer 61

Distal convoluted tubule

Question 62

Where does PTH act

Answer 62

Distal convoluted tubule

Question 63

Where do carbonic anhydrase inhibitors act

Answer 63

Proximal tubule

Question 64

What is the action of carbonic anhydrase inhibitors

Answer 64

Causes bicarbonate loss

Question 65

where do ADH and ANP act

Answer 65

Collecting duct

Question 66

where are aquaporin receptors found

Answer 66

apical membrane

Question 67

Is distal tubular fluid hypo/hyper osmolar

Answer 67

hypo

Question 68

relationship between atrial pressure and ADH

Answer 68

Decreased pressure, Increased ADH

Question 69

affect of Nicotine on ADH

Answer 69

Stimulates ADH release

Question 70

affect of alcohol on ADH

Answer 70

Inhibits ADH release

Question 71

where is H+ secreted

Answer 71

distal convoluted tubule

Question 72

which is more alkali arterial or venous blood

Answer 72

arterial

Question 73

average ph of blood

Answer 73

7.4