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1l the quest for political stability: germany, 1871-1991
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Biology
1 Dec 2025
78
2 pages
Ellie Wood @elliewood_vugw
This practical guide explores how to measure membrane permeability using beetroot cells. You'll learn how to conduct a... Show more
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!
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.
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.
You can download the app from Google Play Store and Apple App Store.
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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Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore essential topics from the AQA November 2021 Higher Tier Biology Paper 1, including heart disease, photosynthesis, plant transport systems, and pathogen biology. This resource provides insights into cellular respiration, cardiovascular treatments, and the role of proteins, fats, and carbohydrates in living organisms. Ideal for exam preparation and understanding key biological processes.
BiologyExplore key concepts from the 2018 OCR GCSE Biology Higher Paper 1, including DNA isolation, plant structures, hormonal control, and the menstrual cycle. This summary covers essential topics such as photosynthesis, osmoregulation, and the human nervous system, providing a comprehensive overview for effective exam preparation.
BiologyExplore key concepts from the GCSE Combined Science Trilogy Higher Tier Biology Paper 1 (May 12, 2020). This resource covers essential topics such as diffusion, osmosis, photosynthesis, enzyme function, and disease prevention, providing detailed answers and explanations to enhance your understanding and exam preparation.
BiologyExplore key concepts in immunology, plant structure, and physiological processes. This summary covers the immune response, circulatory and digestive systems, monoclonal antibodies, and plant transport mechanisms, including xylem and phloem. Ideal for students preparing for higher-tier biology exams.
BiologyExplore the roles of xylem and phloem in plant transport. This summary covers how water and sucrose are transported through plants, detailing the structure and function of these vascular tissues. Ideal for GCSE Biology students preparing for exams.
BiologyExplore the intricacies of the human circulatory system and plant organization in this comprehensive study note. Covering key concepts such as blood vessels, heart structure, enzyme functions, and plant tissues, this resource is designed for quick revision before exams. Ideal for students preparing for higher-level biology assessments.
BiologyApp Store
Google 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 S
iOS 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 Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
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 S
iOS 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 Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
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.
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
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!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
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.
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.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
3
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore essential topics from the AQA November 2021 Higher Tier Biology Paper 1, including heart disease, photosynthesis, plant transport systems, and pathogen biology. This resource provides insights into cellular respiration, cardiovascular treatments, and the role of proteins, fats, and carbohydrates in living organisms. Ideal for exam preparation and understanding key biological processes.
BiologyExplore key concepts from the 2018 OCR GCSE Biology Higher Paper 1, including DNA isolation, plant structures, hormonal control, and the menstrual cycle. This summary covers essential topics such as photosynthesis, osmoregulation, and the human nervous system, providing a comprehensive overview for effective exam preparation.
BiologyExplore key concepts from the GCSE Combined Science Trilogy Higher Tier Biology Paper 1 (May 12, 2020). This resource covers essential topics such as diffusion, osmosis, photosynthesis, enzyme function, and disease prevention, providing detailed answers and explanations to enhance your understanding and exam preparation.
BiologyExplore key concepts in immunology, plant structure, and physiological processes. This summary covers the immune response, circulatory and digestive systems, monoclonal antibodies, and plant transport mechanisms, including xylem and phloem. Ideal for students preparing for higher-tier biology exams.
BiologyExplore the roles of xylem and phloem in plant transport. This summary covers how water and sucrose are transported through plants, detailing the structure and function of these vascular tissues. Ideal for GCSE Biology students preparing for exams.
BiologyExplore the intricacies of the human circulatory system and plant organization in this comprehensive study note. Covering key concepts such as blood vessels, heart structure, enzyme functions, and plant tissues, this resource is designed for quick revision before exams. Ideal for students preparing for higher-level biology assessments.
BiologyApp Store
Google 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 S
iOS 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 Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
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 S
iOS 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 Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
