The effect of temperature on membrane permeability

Question 1

Briefly outline how you would measure the effect of temperature on membrane permeability

Answer 1

1) Label tubes 20-60 degrees
2) Add distilled water to each tube
3) Put tubes in water bath
4) Cut and dry beetroot cylinders
5) Add cylinders to tubes
6) Remove tube, swirl, remove cylinders
7) Pour remaining liquid into a cuvette
8) Measure the absorption of green light for each temperature and record data
9) Plot a graph of temperature against absorption

Question 2

What graph is plotted when measuring the effect of temperature on membrane permeability?

Answer 2

Temperature against absorption (of green light?!)

Question 3

What piece of equipment is used to measure absorption?

Answer 3

Colorimeter

Question 4

What is the independent variable of this experiment?

Answer 4

Temperature

Question 5

What is the dependent variable?

Answer 5

Absorbance

Question 6

What is a control variable?

Answer 6

Same SA of beetroot

Same volume of distilled water

Question 7

What is the effect of temperature on membrane permeability? Why?

Answer 7

Temp increases, permeability increases, leakage rate increases.

Phospholipid molecules gain kinetic energy, move faster, creating more gaps in the membrane for pigment to escape