This practical guide explores how to measure membrane permeability using...
Biology84 views·Updated 23 Jun 2026·2 pagesInvestigating Membrane Permeability: Practical Method and Risks
Ellie Wood@elliewood_vugw
1
of 2
Measuring Membrane Permeability
Beetroot cells contain a purple pigment called betalain that leaks out when the cell membrane becomes more permeable. This makes beetroot an excellent tool for investigating factors that affect membrane permeability.
To set up this experiment, you'll need to cut beetroot into identical cubes, clean off any initially released pigment, and then subject these cubes to different conditions. If testing temperature effects, place each cube in distilled water at different temperatures . For solvent concentration tests, create a dilution series of ethanol (0%-100%) in distilled water.
After leaving the beetroot cubes in solution for about 20 minutes, filter the samples and measure the amount of pigment released using a colorimeter with a blue filter. The higher the absorbance reading, the more pigment has leaked out, indicating greater membrane permeability.
Quick Tip: The more pigment you can see in the water, the more permeable the membrane has become. This visual indicator makes it easy to see results even before using the colorimeter!
2
of 2
Risk Assessment
When conducting this practical, be aware of several important safety considerations. When using a scalpel to cut the beetroot, always cut away from your fingers and keep the scalpel away from the edge of your desk to prevent accidental cuts.
Glass equipment presents a risk of breakage. Handle all glassware with care and clean up any broken glass promptly and safely. If an accident occurs, don't remove embedded glass—instead, elevate the area, apply pressure, and seek help.
Ethanol used in the experiment is both an irritant and flammable. Always wear eye protection and keep ethanol away from naked flames. For hot liquids in water baths, use tongs to handle test tubes and wear appropriate eye protection to prevent scalding.
Safety First: Most lab accidents happen when students rush or get distracted. Take your time and stay focused on each step of the procedure to keep yourself and your classmates safe.
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Biology84 views·Updated 23 Jun 2026·2 pagesInvestigating Membrane Permeability: Practical Method and Risks
Ellie Wood@elliewood_vugw
This practical guide explores how to measure membrane permeability using beetroot cells. You'll learn how to conduct a simple experiment that shows how different conditions affect how easily substances pass through cell membranes.
1
of 2
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Measuring Membrane Permeability
Beetroot cells contain a purple pigment called betalain that leaks out when the cell membrane becomes more permeable. This makes beetroot an excellent tool for investigating factors that affect membrane permeability.
To set up this experiment, you'll need to cut beetroot into identical cubes, clean off any initially released pigment, and then subject these cubes to different conditions. If testing temperature effects, place each cube in distilled water at different temperatures . For solvent concentration tests, create a dilution series of ethanol (0%-100%) in distilled water.
After leaving the beetroot cubes in solution for about 20 minutes, filter the samples and measure the amount of pigment released using a colorimeter with a blue filter. The higher the absorbance reading, the more pigment has leaked out, indicating greater membrane permeability.
Quick Tip: The more pigment you can see in the water, the more permeable the membrane has become. This visual indicator makes it easy to see results even before using the colorimeter!
2
of 2Sign up to see the content. It's free!
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Risk Assessment
When conducting this practical, be aware of several important safety considerations. When using a scalpel to cut the beetroot, always cut away from your fingers and keep the scalpel away from the edge of your desk to prevent accidental cuts.
Glass equipment presents a risk of breakage. Handle all glassware with care and clean up any broken glass promptly and safely. If an accident occurs, don't remove embedded glass—instead, elevate the area, apply pressure, and seek help.
Ethanol used in the experiment is both an irritant and flammable. Always wear eye protection and keep ethanol away from naked flames. For hot liquids in water baths, use tongs to handle test tubes and wear appropriate eye protection to prevent scalding.
Safety First: Most lab accidents happen when students rush or get distracted. Take your time and stay focused on each step of the procedure to keep yourself and your classmates safe.
We thought you’d never ask...
What is the Knowunity AI companion?
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
Where can I download the Knowunity app?
You can download the app from Google Play Store and Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
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Students love us — and so will you.
4.6/5App Store
4.7/5Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan SiOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha KlichAndroid user
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