RP4,membrane☘️🧑🏾🔬 Flashcards
List 5 competences on practicals
-follow instructions
-apply investigate appropriate methods
-safely use range of practical equipment and material
-collect results
-make observations
-research,references and report
Tell me the steps to get colour standards
1-use 5 test tube and in one you put 5,4,3,2,1 cm cube of distilled water then using pipette take 1,2,3,4,5 cm cube of beet root or ethanol.
2-using a colorimeter,remove cubette and use pippet to remove a sample of earth of the 5 pippetes
3-record the absorption from colorimeter
(To see if the colorimeter works properly add 5cm cube of distilled water in and it should show 0.00 and if doesn’t press calc which will calibrate it to be right)
State the equipment needed for investigation of cell membrane permeability
-cut 3 up to 10 identical cubes of beetroot using scapel and (small knife,ruler) and cutting board
-wipe to clean off any pigment released as a result
-temperature:add equally volumes of distilled water
-set up with heatproof mat,Bunsen burner,water bath,tripod and heat the water baths to a specific temperature like 50(blue flame)
-then remove your test tubes and add beetroot to watch of them and put them in water bath(leave for 15 minutes)
-set colorimeter you blue filter and zero using a cuvette with distilled water(0.00) should show
-and out a sample of each test tube into the cuvette and read the absorption
-higher number means higher pigment concentration this a more permeable membrane
Risk assessment (cell membrane permeability)
-Ethanol is flammable so get it away from fire and skin (colour standards)
-hot test tube can burn fingers so we need to get it from the top and not side
- knife can cut skin so when cutting her knife away from skin
Why is important to keep water volume same?
ensures a consistent environment for the experiment. This control variable helps isolate the effects of the independent variable (e.g., temperature, pH) on the cell membrane permeability.
