Maths
Chemistry
Biology
English Language
History
Responding to change (a2 only)
Infection and response
Homeostasis and response
Energy transfers (a2 only)
Cell biology
Organisms respond to changes in their internal and external environments (a-level only)
Biological molecules
Organisation
Substance exchange
Bioenergetics
Genetic information & variation
Inheritance, variation and evolution
Genetics & ecosystems (a2 only)
Ecology
Cells
Show all topics
Britain & the wider world: 1745 -1901
1l the quest for political stability: germany, 1871-1991
The cold war
Inter-war germany
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
World war two & the holocaust
2n revolution and dictatorship: russia, 1917-1953
2s the making of modern britain, 1951-2007
World war one
Britain: 1509 -1745
Show all topics
Biology
2 Dec 2025
160
3 pages
Milkshakemi @milkshakemi
Ever wondered how your body manages to be so organised and efficient? It all starts with cell specialisation... Show more
Your body is basically a massive team project, and cell specialisation is how everyone gets their specific job assignment. Every cell in your body started as an identical copy from that very first fertilised egg, containing exactly the same DNA blueprint.
Here's the clever bit even though all cells have the same genes, different genes get switched on or off in each cell type. It's like having the same recipe book but choosing to make completely different dishes. A nerve cell activates genes for electrical signaling, while a muscle cell focuses on genes for contraction.
Specialised cells develop unique structures and organelles that match their function perfectly. Think of it like a toolbox - a muscle cell packs itself with protein fibres for movement, whilst a white blood cell loads up on enzymes for fighting infections.
Quick Tip Remember that specialisation = efficiency. Each cell becomes brilliant at one job rather than being average at everything!
Once you've got specialised cells, life gets even more organised by grouping similar cells into tissues. Think of tissues as departments in a company - everyone has the same basic skill set and works towards the same goal.
Epithelial tissue in animals forms protective sheets that line your organs, like the inside of your mouth. In plants, xylem tissue acts like a plumbing system, transporting water and minerals throughout the plant using specialised tube-like cells.
The next level up is organs - combinations of different tissues working as a coordinated team. Your stomach is a perfect example, combining muscle tissue (for churning food), epithelial tissue (for protection and secretion), and connective tissue (holding everything together).
Plant organs work similarly. A leaf combines xylem (water transport), phloem (sugar transport), palisade mesophyll (photosynthesis), and spongy mesophyll (gas exchange) to create an efficient food-making factory.
Remember Tissues = similar cells with same job; Organs = different tissues with coordinated jobs!
The ultimate level of organisation is organ systems - multiple organs joining forces like a superhero team. Each system tackles a major life function that no single organ could handle alone.
Your digestive system is probably the most relatable example. It includes your salivary glands, oesophagus, stomach, small intestine, pancreas, and liver all working together to break down that sandwich you had for lunch and extract the nutrients your body needs.
The respiratory system (trachea, bronchi, lungs) specialises in gas exchange, making sure oxygen gets in and carbon dioxide gets out. Meanwhile, your circulatory system (heart, arteries, veins) acts like a delivery service, pumping blood and transporting everything your cells need.
What's brilliant is how these systems coordinate with each other. Your respiratory system loads oxygen into blood, your circulatory system delivers it to cells, and your digestive system provides the fuel to keep everything running.
Key Point Organ systems prove that teamwork really does make the dream work - each system depends on others to keep you alive and healthy!
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.
2
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the organization of plant cells, including detailed descriptions of various plant tissues such as xylem, phloem, and mesophyll. Understand how these tissues function in leaf anatomy and contribute to plant survival and growth. This summary is ideal for students studying plant biology.
BiologyExplore the concept of diffusion in this concise summary, perfect for Year 9-10 biology students. Learn about high and low concentration areas, concentration gradients, and real-life examples like perfume dispersal. This resource is ideal for revision and understanding key biological processes.
BiologyExplore key concepts in GCSE AQA Biology Paper 1, including cellular structure, functions, photosynthesis, and respiration. This summary provides a clear understanding of essential topics for exam preparation.
BiologyExplore key concepts in biology, including antibiotic resistance, cell diffusion, the digestive system, and the structure of the heart. This summary provides essential information on enzymes, diseases, and microscopy techniques, perfect for AQA exam preparation. Enhance your understanding of biological processes and systems with this concise overview.
BiologyExplore the anatomy of the heart, including its chambers and valves, alongside an in-depth look at coronary heart disease and its treatments. This resource features a detailed diagram and discusses interventions like stents, artificial pacemakers, and valve replacements. Ideal for AQA Biology students.
BiologyExplore the organization of plant cells, including vascular tissues like xylem and phloem, and their roles in nutrient transport and photosynthesis. This summary covers key concepts such as transpiration, stomata function, and the impact of environmental factors on plant health. Ideal for GCSE Biology revision.
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
Milkshakemi
@milkshakemi
Ever wondered how your body manages to be so organised and efficient? It all starts with cell specialisation- the amazing process where identical cells transform into specialists with unique jobs. From there, life builds up through increasingly complex levels... Show more
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Your body is basically a massive team project, and cell specialisation is how everyone gets their specific job assignment. Every cell in your body started as an identical copy from that very first fertilised egg, containing exactly the same DNA blueprint.
Here's the clever bit: even though all cells have the same genes, different genes get switched on or off in each cell type. It's like having the same recipe book but choosing to make completely different dishes. A nerve cell activates genes for electrical signaling, while a muscle cell focuses on genes for contraction.
Specialised cells develop unique structures and organelles that match their function perfectly. Think of it like a toolbox - a muscle cell packs itself with protein fibres for movement, whilst a white blood cell loads up on enzymes for fighting infections.
Quick Tip: Remember that specialisation = efficiency. Each cell becomes brilliant at one job rather than being average at everything!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Once you've got specialised cells, life gets even more organised by grouping similar cells into tissues. Think of tissues as departments in a company - everyone has the same basic skill set and works towards the same goal.
Epithelial tissue in animals forms protective sheets that line your organs, like the inside of your mouth. In plants, xylem tissue acts like a plumbing system, transporting water and minerals throughout the plant using specialised tube-like cells.
The next level up is organs - combinations of different tissues working as a coordinated team. Your stomach is a perfect example, combining muscle tissue (for churning food), epithelial tissue (for protection and secretion), and connective tissue (holding everything together).
Plant organs work similarly. A leaf combines xylem (water transport), phloem (sugar transport), palisade mesophyll (photosynthesis), and spongy mesophyll (gas exchange) to create an efficient food-making factory.
Remember: Tissues = similar cells with same job; Organs = different tissues with coordinated jobs!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
The ultimate level of organisation is organ systems - multiple organs joining forces like a superhero team. Each system tackles a major life function that no single organ could handle alone.
Your digestive system is probably the most relatable example. It includes your salivary glands, oesophagus, stomach, small intestine, pancreas, and liver all working together to break down that sandwich you had for lunch and extract the nutrients your body needs.
The respiratory system (trachea, bronchi, lungs) specialises in gas exchange, making sure oxygen gets in and carbon dioxide gets out. Meanwhile, your circulatory system (heart, arteries, veins) acts like a delivery service, pumping blood and transporting everything your cells need.
What's brilliant is how these systems coordinate with each other. Your respiratory system loads oxygen into blood, your circulatory system delivers it to cells, and your digestive system provides the fuel to keep everything running.
Key Point: Organ systems prove that teamwork really does make the dream work - each system depends on others to keep you alive and healthy!
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.
2
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the organization of plant cells, including detailed descriptions of various plant tissues such as xylem, phloem, and mesophyll. Understand how these tissues function in leaf anatomy and contribute to plant survival and growth. This summary is ideal for students studying plant biology.
BiologyExplore the concept of diffusion in this concise summary, perfect for Year 9-10 biology students. Learn about high and low concentration areas, concentration gradients, and real-life examples like perfume dispersal. This resource is ideal for revision and understanding key biological processes.
BiologyExplore key concepts in GCSE AQA Biology Paper 1, including cellular structure, functions, photosynthesis, and respiration. This summary provides a clear understanding of essential topics for exam preparation.
BiologyExplore key concepts in biology, including antibiotic resistance, cell diffusion, the digestive system, and the structure of the heart. This summary provides essential information on enzymes, diseases, and microscopy techniques, perfect for AQA exam preparation. Enhance your understanding of biological processes and systems with this concise overview.
BiologyExplore the anatomy of the heart, including its chambers and valves, alongside an in-depth look at coronary heart disease and its treatments. This resource features a detailed diagram and discusses interventions like stents, artificial pacemakers, and valve replacements. Ideal for AQA Biology students.
BiologyExplore the organization of plant cells, including vascular tissues like xylem and phloem, and their roles in nutrient transport and photosynthesis. This summary covers key concepts such as transpiration, stomata function, and the impact of environmental factors on plant health. Ideal for GCSE Biology revision.
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
Sociology