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Britain & the wider world: 1745 -1901
1l the quest for political stability: germany, 1871-1991
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Inter-war germany
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2d religious conflict and the church in england, c1529-c1570
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1f industrialisation and the people: britain, c1783-1885
1c the tudors: england, 1485-1603
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Biology
7 Dec 2025
227
2 pages
Osmosis is a key biological process that impacts how cells interact with their environment. It involves the movement... Show more
Osmosis is a special type of diffusion that focuses specifically on water movement. While diffusion is the movement of any particles from higher to lower concentration areas, osmosis refers only to water molecules moving through a partially permeable membrane.
Water always moves from a dilute solution (where there's more water) to a concentrated solution (where there's less water). Think of it as water trying to balance things out by moving to where it's needed most. The membrane acts like a security guard, letting some molecules through but blocking others.
Cell osmosis happens because the cytoplasm inside cells is typically a concentrated solution with relatively low water concentration. When a cell is placed in plain water, water molecules move into the cell through osmosis because there's more water outside than inside.
Quick Tip Remember that osmosis is always about water movement, not other molecules. Water flows from "more water" to "less water" areas, which isn't always intuitive at first!
Animal cells respond dramatically to their environment through osmosis. In a hypotonic solution (more dilute than the cell), water rushes in and can cause the cell to swell and potentially burst. In a hypertonic solution (more concentrated), water leaves the cell, causing it to shrink and potentially lose function.
When a cell is in an isotonic solution with the same concentration as the cell interior, no net movement of water occurs. This balanced state is ideal for most animal cells, as it prevents damage from excessive swelling or shrinking.
Plant cells respond differently to osmosis due to their rigid cell wall. In water (hypotonic solution), a plant cell takes in water and becomes turgid (swollen and firm), but the cell wall prevents it from bursting. This turgidity actually helps plants stand upright!
When placed in a concentrated solution, plant cells lose water and become flaccid as the cell membrane pulls away from the cell wall. This is why plants wilt when they don't get enough waterโtheir cells have lost that crucial internal pressure.
Remember The cell wall is the key difference between plant and animal cell responses to osmosisโit protects plant cells from bursting when they take in too much water.
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.
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Explore essential concepts in DNA and genetic inheritance, including dominant and recessive alleles, genotypes, phenotypes, and how to effectively use Punnett squares to predict offspring traits. This summary provides clear definitions and practical examples for students studying Mendelian genetics.
BiologyExplore the principles of genetic inheritance, including dominant and recessive alleles, genotypes, and phenotypes. This resource covers predicting outcomes of genetic crosses using Punnett squares, with practical examples and questions to enhance understanding. Ideal for GCSE students studying genetics.
BiologyCovers everything on the specification! For GCSE Biology students (triple+higher) AQA exam board :) Will post these for every topic in science.
BiologyExplore the key concepts of genetic and environmental variation, the role of DNA and chromosomes, and the differences between sexual and asexual reproduction. This summary is essential for AQA Biology students aiming for top grades in combined, higher, and triple biology courses.
BiologyExplore the fundamentals of genetic inheritance, including meiosis, gamete formation, and the role of DNA in heredity. This summary covers key concepts such as variation, alleles, and the implications of genetic screening. Ideal for biology students preparing for exams or seeking to understand human heredity.
BiologyExplore the principles of genetic variation and inheritance, including monohybrid crosses, Punnett squares, and key genetic terms such as allele, genotype, and phenotype. This summary covers discrete and continuous variation, Mendelian genetics, and the impact of dominant and recessive alleles on inheritance patterns. Ideal for N5 biology students preparing for exams.
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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
Osmosis is a key biological process that impacts how cells interact with their environment. It involves the movement of water molecules across membranes based on concentration differences, which affects cell structure and function in both plants and animals.
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Osmosis is a special type of diffusion that focuses specifically on water movement. While diffusion is the movement of any particles from higher to lower concentration areas, osmosis refers only to water molecules moving through a partially permeable membrane.
Water always moves from a dilute solution (where there's more water) to a concentrated solution (where there's less water). Think of it as water trying to balance things out by moving to where it's needed most. The membrane acts like a security guard, letting some molecules through but blocking others.
Cell osmosis happens because the cytoplasm inside cells is typically a concentrated solution with relatively low water concentration. When a cell is placed in plain water, water molecules move into the cell through osmosis because there's more water outside than inside.
Quick Tip: Remember that osmosis is always about water movement, not other molecules. Water flows from "more water" to "less water" areas, which isn't always intuitive at first!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Animal cells respond dramatically to their environment through osmosis. In a hypotonic solution (more dilute than the cell), water rushes in and can cause the cell to swell and potentially burst. In a hypertonic solution (more concentrated), water leaves the cell, causing it to shrink and potentially lose function.
When a cell is in an isotonic solution with the same concentration as the cell interior, no net movement of water occurs. This balanced state is ideal for most animal cells, as it prevents damage from excessive swelling or shrinking.
Plant cells respond differently to osmosis due to their rigid cell wall. In water (hypotonic solution), a plant cell takes in water and becomes turgid (swollen and firm), but the cell wall prevents it from bursting. This turgidity actually helps plants stand upright!
When placed in a concentrated solution, plant cells lose water and become flaccid as the cell membrane pulls away from the cell wall. This is why plants wilt when they don't get enough waterโtheir cells have lost that crucial internal pressure.
Remember: The cell wall is the key difference between plant and animal cell responses to osmosisโit protects plant cells from bursting when they take in too much water.
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 โ all at your fingertips.
8
Smart Tools NEW
Transform this note into: โ 50+ Practice Questions โ Interactive Flashcards โ Full Mock Exam โ Essay Outlines
Explore essential concepts in DNA and genetic inheritance, including dominant and recessive alleles, genotypes, phenotypes, and how to effectively use Punnett squares to predict offspring traits. This summary provides clear definitions and practical examples for students studying Mendelian genetics.
BiologyExplore the principles of genetic inheritance, including dominant and recessive alleles, genotypes, and phenotypes. This resource covers predicting outcomes of genetic crosses using Punnett squares, with practical examples and questions to enhance understanding. Ideal for GCSE students studying genetics.
BiologyCovers everything on the specification! For GCSE Biology students (triple+higher) AQA exam board :) Will post these for every topic in science.
BiologyExplore the key concepts of genetic and environmental variation, the role of DNA and chromosomes, and the differences between sexual and asexual reproduction. This summary is essential for AQA Biology students aiming for top grades in combined, higher, and triple biology courses.
BiologyExplore the fundamentals of genetic inheritance, including meiosis, gamete formation, and the role of DNA in heredity. This summary covers key concepts such as variation, alleles, and the implications of genetic screening. Ideal for biology students preparing for exams or seeking to understand human heredity.
BiologyExplore the principles of genetic variation and inheritance, including monohybrid crosses, Punnett squares, and key genetic terms such as allele, genotype, and phenotype. This summary covers discrete and continuous variation, Mendelian genetics, and the impact of dominant and recessive alleles on inheritance patterns. Ideal for N5 biology students preparing for exams.
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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