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Britain & the wider world: 1745 -1901
1l the quest for political stability: germany, 1871-1991
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Medieval period: 1066 -1509
2d religious conflict and the church in england, c1529-c1570
2o democracy and nazism: germany, 1918-1945
1f industrialisation and the people: britain, c1783-1885
1c the tudors: england, 1485-1603
2m wars and welfare: britain in transition, 1906-1957
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2s the making of modern britain, 1951-2007
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Biology
8 Dec 2025
387
2 pages
cara @carajulia
Ever wondered why chips go soggy when you leave them out, or why your fingers wrinkle in the... Show more
You'll be investigating osmosis - the movement of water molecules from areas of high concentration to low concentration through a semi-permeable membrane. Think of it like water always trying to balance itself out on both sides of a barrier.
Start by cutting five identical potato cylinders using a cork borer, then trim the ends so they're all exactly the same length. Weigh each cylinder carefully - accuracy matters here! You'll need five different concentrations of sugar solution in separate test tubes, from pure water to a strong sugar solution .
Pop one potato cylinder into each tube and leave them for the same amount of time. When you remove them, blot them dry before weighing - any surface water will mess up your results.
Top Tip Keep your potato cylinders the same size and timing consistent - small changes can throw off your entire experiment!
The magic happens when water moves to balance concentrations on both sides of the potato cell membranes. In distilled water, your potato gained 16.2% mass because water rushed into the cells where sugar concentration was higher - this is called a hypotonic solution.
As sugar concentration increases outside the potato, less water moves in. Eventually, you'll hit a point where water actually leaves the potato cells. In the strongest solutions, the potato lost 9% of its mass because the outside solution was hypertonic - more concentrated than inside the cells.
The graph shows this perfectly - mass gain drops steadily until it crosses zero, then becomes mass loss. Where the line crosses zero tells you the concentration that matches inside the potato cells.
Exam Smart Remember that water always moves towards higher solute concentration - if there's more sugar outside, water moves out of the potato!
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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Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore key concepts in GCSE AQA Biology, focusing on human and plant systems. This summary covers the circulatory system, blood components, digestive enzymes, and plant transport mechanisms, including xylem and phloem. Ideal for exam preparation, it includes essential diagrams and detailed explanations of cardiovascular treatments and plant tissue organization.
BiologyExplore essential practical investigations in Biology, including enzyme activity, osmosis in plant tissues, and microscopy techniques. This resource covers the equipment, procedures, and expected results for experiments on amylase, potato osmosis, and cellular structures. Ideal for AQA GCSE students preparing for Paper 1.
BiologyExplore key exam questions and concepts related to cell structure, including human and plant cells, cellular processes, and the roles of organelles like ribosomes and mitochondria. This summary covers essential topics for understanding cellular organization and function, ideal for exam preparation.
BiologyExplore key concepts in osmosis, binary fission, and microscopy with this detailed summary. Understand how water movement affects cells, the process of bacterial population growth, and essential food tests for carbohydrates, proteins, and lipids. Ideal for GCSE AQA Science students.
BiologyExplore key concepts in National 5 Biology Unit 1, including cell structure, enzyme function, genetic engineering, and transport mechanisms. This summary covers essential topics such as osmosis, DNA structure, and the role of enzymes in digestion, providing a comprehensive resource for exam preparation.
BiologyExplore the osmosis process through a hands-on potato experiment. This practical guide details the steps to investigate how different sucrose concentrations affect potato mass, including calculations for percentage change. Ideal for GCSE Biology students and anyone studying diffusion, osmosis, and tonicity concepts.
BiologyQuotes from every main character
English LiteratureApp 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
cara
@carajulia
Ever wondered why chips go soggy when you leave them out, or why your fingers wrinkle in the bath? It's all down to osmosis - the movement of water through cell membranes. This practical investigation shows you exactly how to... Show more
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
You'll be investigating osmosis - the movement of water molecules from areas of high concentration to low concentration through a semi-permeable membrane. Think of it like water always trying to balance itself out on both sides of a barrier.
Start by cutting five identical potato cylinders using a cork borer, then trim the ends so they're all exactly the same length. Weigh each cylinder carefully - accuracy matters here! You'll need five different concentrations of sugar solution in separate test tubes, from pure water to a strong sugar solution .
Pop one potato cylinder into each tube and leave them for the same amount of time. When you remove them, blot them dry before weighing - any surface water will mess up your results.
Top Tip: Keep your potato cylinders the same size and timing consistent - small changes can throw off your entire experiment!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
The magic happens when water moves to balance concentrations on both sides of the potato cell membranes. In distilled water, your potato gained 16.2% mass because water rushed into the cells where sugar concentration was higher - this is called a hypotonic solution.
As sugar concentration increases outside the potato, less water moves in. Eventually, you'll hit a point where water actually leaves the potato cells. In the strongest solutions, the potato lost 9% of its mass because the outside solution was hypertonic - more concentrated than inside the cells.
The graph shows this perfectly - mass gain drops steadily until it crosses zero, then becomes mass loss. Where the line crosses zero tells you the concentration that matches inside the potato cells.
Exam Smart: Remember that water always moves towards higher solute concentration - if there's more sugar outside, water moves out of the potato!
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.
4
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore key concepts in GCSE AQA Biology, focusing on human and plant systems. This summary covers the circulatory system, blood components, digestive enzymes, and plant transport mechanisms, including xylem and phloem. Ideal for exam preparation, it includes essential diagrams and detailed explanations of cardiovascular treatments and plant tissue organization.
BiologyExplore essential practical investigations in Biology, including enzyme activity, osmosis in plant tissues, and microscopy techniques. This resource covers the equipment, procedures, and expected results for experiments on amylase, potato osmosis, and cellular structures. Ideal for AQA GCSE students preparing for Paper 1.
BiologyExplore key exam questions and concepts related to cell structure, including human and plant cells, cellular processes, and the roles of organelles like ribosomes and mitochondria. This summary covers essential topics for understanding cellular organization and function, ideal for exam preparation.
BiologyExplore key concepts in osmosis, binary fission, and microscopy with this detailed summary. Understand how water movement affects cells, the process of bacterial population growth, and essential food tests for carbohydrates, proteins, and lipids. Ideal for GCSE AQA Science students.
BiologyExplore key concepts in National 5 Biology Unit 1, including cell structure, enzyme function, genetic engineering, and transport mechanisms. This summary covers essential topics such as osmosis, DNA structure, and the role of enzymes in digestion, providing a comprehensive resource for exam preparation.
BiologyExplore the osmosis process through a hands-on potato experiment. This practical guide details the steps to investigate how different sucrose concentrations affect potato mass, including calculations for percentage change. Ideal for GCSE Biology students and anyone studying diffusion, osmosis, and tonicity concepts.
BiologyQuotes from every main character
English LiteratureApp 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
Sociology