Subjects
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
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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
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Biology
29 Nov 2025
398
3 pages
Jenni H @enni_mdxm
Every living thing is made up of cells - the basic building blocks of life. Understanding different cell... Show more
You'll encounter three main types of cells in biology, each with distinct features that help them survive. Animal cells and plant cells are both eukaryotic cells, meaning they're complex and have a proper nucleus. Bacteria cells are prokaryotic cells - much simpler, single-celled organisms without a true nucleus.
All cells share some basic components like the cell membrane (controls what enters and exits), cytoplasm , and ribosomes (protein factories). The nucleus in animal and plant cells acts like the control centre, storing DNA and managing cell activities.
Plant cells have three extra features that animal cells lack chloroplasts for photosynthesis, a vacuole for storing sap and energy, and a cell wall for extra protection. Mitochondria are the powerhouses in both animal and plant cells, releasing energy through respiration.
Quick tip Remember that plant cells have everything animal cells have, PLUS chloroplasts, vacuole, and cell wall!
Bacteria cells have unique structures like flagella for movement, a capsule for protection, and plasmids - small DNA pieces that copy genes. The nucleoid DNA controls activities without being enclosed in a nucleus like eukaryotic cells.
Cell differentiation is how cells change to become specialised for specific jobs. Sperm cells are perfectly designed for fertilisation with their streamlined shape, energy-packed mitochondria, and 23 chromosomes ready to combine with an egg.
Muscle cells contain protein filaments that contract and relax, plus loads of mitochondria to power movement. Nerve cells have an incredibly long structure with dendrites, axon, and myelin sheath to carry electrical impulses around your body at lightning speed.
Remember Each specialised cell's structure directly relates to its function - form follows function!
Root hair cells are plant cells with a genius design for absorption. Their long, thin projections dramatically increase surface area, allowing more water and nutrients to move into the plant from soil. They're packed with mitochondria because active transport requires lots of energy.
Red blood cells are your body's oxygen delivery service. They're crammed with haemoglobin to carry oxygen around your body and transport carbon dioxide back to your lungs for removal. These cells have no nucleus, creating more space for oxygen transport.
The mitochondria in root hair cells work overtime, releasing energy from glucose through respiration to power the active transport process. This energy-demanding system allows plants to extract nutrients efficiently from soil, even when concentrations are low.
Key insight Specialised cells sacrifice some features to excel at their main job - red blood cells lose their nucleus for maximum oxygen capacity!
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 the essential concepts of cellular structures, transport mechanisms, and enzyme functions in this comprehensive study note. Covering key topics such as osmosis, diffusion, active transport, and microscopy, this resource is designed for GCSE WJEC Biology students to enhance their understanding of cell organization and function. Ideal for exam preparation and revision.
BiologyExplore the fundamental concepts of cell biology, including cell structure, function, and specialization. This summary covers key topics such as prokaryotic and eukaryotic cells, specialized animal and plant cells, binary fission, and microscopy techniques. Ideal for students preparing for exams or seeking a comprehensive overview of cellular processes.
Biologyuseful knowledge
BiologyExplore the intricate processes of digestion, including the roles of enzymes, adaptations of digestive organs, and mechanisms of nutrient transport. This summary covers key concepts such as peristalsis, enzyme functions, and the differences between diffusion, osmosis, and active transport, providing a comprehensive overview for students studying human digestion.
Biologydiffusion +osmosis, plant cell+animal cell, microscopy, transport in cells,
BiologyExplore the concept of animal cell specialization and differentiation. This summary covers the roles of nerve cells, muscle cells, and sperm cells, detailing their structures and functions. Understand how these specialized cells contribute to overall body function and the process of fertilization. Ideal for biology students studying cell biology.
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
Jenni H
@enni_mdxm
Every living thing is made up of cells - the basic building blocks of life. Understanding different cell types and their specialised functions is crucial for grasping how organisms survive and thrive.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
You'll encounter three main types of cells in biology, each with distinct features that help them survive. Animal cells and plant cells are both eukaryotic cells, meaning they're complex and have a proper nucleus. Bacteria cells are prokaryotic cells - much simpler, single-celled organisms without a true nucleus.
All cells share some basic components like the cell membrane (controls what enters and exits), cytoplasm , and ribosomes (protein factories). The nucleus in animal and plant cells acts like the control centre, storing DNA and managing cell activities.
Plant cells have three extra features that animal cells lack: chloroplasts for photosynthesis, a vacuole for storing sap and energy, and a cell wall for extra protection. Mitochondria are the powerhouses in both animal and plant cells, releasing energy through respiration.
Quick tip: Remember that plant cells have everything animal cells have, PLUS chloroplasts, vacuole, and cell wall!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Bacteria cells have unique structures like flagella for movement, a capsule for protection, and plasmids - small DNA pieces that copy genes. The nucleoid DNA controls activities without being enclosed in a nucleus like eukaryotic cells.
Cell differentiation is how cells change to become specialised for specific jobs. Sperm cells are perfectly designed for fertilisation with their streamlined shape, energy-packed mitochondria, and 23 chromosomes ready to combine with an egg.
Muscle cells contain protein filaments that contract and relax, plus loads of mitochondria to power movement. Nerve cells have an incredibly long structure with dendrites, axon, and myelin sheath to carry electrical impulses around your body at lightning speed.
Remember: Each specialised cell's structure directly relates to its function - form follows function!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Root hair cells are plant cells with a genius design for absorption. Their long, thin projections dramatically increase surface area, allowing more water and nutrients to move into the plant from soil. They're packed with mitochondria because active transport requires lots of energy.
Red blood cells are your body's oxygen delivery service. They're crammed with haemoglobin to carry oxygen around your body and transport carbon dioxide back to your lungs for removal. These cells have no nucleus, creating more space for oxygen transport.
The mitochondria in root hair cells work overtime, releasing energy from glucose through respiration to power the active transport process. This energy-demanding system allows plants to extract nutrients efficiently from soil, even when concentrations are low.
Key insight: Specialised cells sacrifice some features to excel at their main job - red blood cells lose their nucleus for maximum oxygen capacity!
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.
5
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the essential concepts of cellular structures, transport mechanisms, and enzyme functions in this comprehensive study note. Covering key topics such as osmosis, diffusion, active transport, and microscopy, this resource is designed for GCSE WJEC Biology students to enhance their understanding of cell organization and function. Ideal for exam preparation and revision.
BiologyExplore the fundamental concepts of cell biology, including cell structure, function, and specialization. This summary covers key topics such as prokaryotic and eukaryotic cells, specialized animal and plant cells, binary fission, and microscopy techniques. Ideal for students preparing for exams or seeking a comprehensive overview of cellular processes.
Biologyuseful knowledge
BiologyExplore the intricate processes of digestion, including the roles of enzymes, adaptations of digestive organs, and mechanisms of nutrient transport. This summary covers key concepts such as peristalsis, enzyme functions, and the differences between diffusion, osmosis, and active transport, providing a comprehensive overview for students studying human digestion.
Biologydiffusion +osmosis, plant cell+animal cell, microscopy, transport in cells,
BiologyExplore the concept of animal cell specialization and differentiation. This summary covers the roles of nerve cells, muscle cells, and sperm cells, detailing their structures and functions. Understand how these specialized cells contribute to overall body function and the process of fertilization. Ideal for biology students studying cell biology.
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