Variant 2- transport through artificail membrane

Question 1

Questions concerning Transport of substances through artificial membrane
1. The aim of the study (5)

Answer 1

To determine the coefficient of permeability of an artificial membrane for a given
substance

Question 1

Write the equation for concentration decay of Cl- with time -Logarithmic formula. Explain the
parameters involved (7)

Look in answers

Answer 1

Conc. At time t and at time 0, V volume of the dialyzed solution, S area of the
membrane where dialysis occurs, P membrane permeability

Question 2

Describe shortly the experimental work and measurements performed in this practice. Show
on a graph how the halftime of the concentration decay (8)

also its the graph where its decends
plot time on x axis(top) and log c on y

Answer 2

Fill 200ml NaCl solution in a flask for dialysis
* Two channel peristaltic pump circulates the solution through the lumen of the fine
capillaries in the dialysis column and back to the flask
* The other side of the membrane it pumps distilled water which goes to the waste
flask
* So we hold the concentration on the one side of the membrane close to zero
* We take 2ml from the dialysed solution every 5 mins
* Follow up of the concentration decay lasts about 30 mins
* Represent the plot over time

Question 3

Which formula can you use to estimate the time for haemodialysis of concrete patient

Answer 3

look at answer

Question 4

Given below is the formula for the facilitated diffusion. Explain the parameter and represent
it graphically. Show on the graph the point for Km (9)

Answer 4

• J max - Max flux
• Km - Michaelis constant
• C - Concentration

Graph Where jmax/2 is km

Question 5

Write the Henderson’s equation for the dependence of the diffusion potential on the
concentration gradient and explain the physical meaning of the parameters involved (9)

Answer 5

Pd=(u+ - u-/u+ + u- ) RT/zF lnC1/C2

Question 6

Which parameter is used for comparison of the acidic resistance of different blood samples.
Give examples of disease, which can be screened with such type of tests (3)

Answer 6

The time for 50% haemolysis is used for comparison of the acidic resistance of
different blood samples
* Haemolytic anaemia can be screened with this test as resistance of RBC is decreased

Question 7

Plot the dependence of the diffusion potential(Ed) on the concentration gradient (lgC1/C2)
(5)

Answer 7

linear graph

Question 8

Calculate the numerical value of the slope a for the Henderson’s equation using the results in
the table (5)

Answer 8

same as variant 1 use 35, 65, 90 and use that weird hendersons slope equstion

Question 9

Calculate the following parameter (4)

Answer 9

9x10-4

Question 10

Write the equation for determination of the electrophoretic mobility. Explain the parameters
involved (8)

Answer 10

U=V/E

V= electrophoretic velocity
E= electric firld strength

U=l.s/I.p.T
p=rho specific reisstance

Question 11

Represent in a graph the time course of absorbance during haemolysis. Show on the plot
how the time for 50% haemolysis (t50%) is determined (6)

Answer 11

Descending curve

Question 12

Plot the dependence of the relative volume of erythrocyte (V) on the osmotic pressure (1/O)

Answer 12

linear graph

Question 13

Determine the osmotically inert volume on the graph above (5)

Answer 13

Extrapolate the line until it reaches the Y axis
* Osmotically inert means there is no osmotic pressure for this volume