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
3 Dec 2025
51
3 pages
Gen J @genj_nuom
Every living thing on Earth is made up of cells, but not all cells are created equal. Understanding... Show more
You'll find eukaryotic cells in animals, plants, fungi, and protists - basically everything you can see without a microscope. What makes these cells special is their sophisticated internal organisation that's like having different departments in a factory.
The most defining feature is the true nucleus, which acts as the cell's control centre. It's surrounded by a protective nuclear envelope with tiny gates called nuclear pores that control what goes in and out. Think of it as a high-security office where all the important genetic information is stored safely.
Membrane-bound organelles are what really set eukaryotic cells apart. The Smooth Endoplasmic Reticulum (Smooth ER) looks like a series of flattened pancakes and specialises in making steroids and lipids. Meanwhile, the Rough ER does the same job but has ribosomes stuck to its surface, making it look bumpy under a microscope.
Quick Tip Remember that "eu" means "true" in Greek - so eukaryotes have a "true nucleus"!
The Rough ER isn't just about looking bumpy - those attached ribosomes are protein-making machines. Once proteins are made, they fold into their proper 3D shapes inside the ER, like origami finding its final form.
Centrioles become the stars during cell division, producing spindle fibres that grab onto replicated chromosomes and pull them apart during mitosis. Inside the nucleus, the nucleolus works as the ribosome factory, constantly churning out these essential protein-makers.
The Golgi apparatus acts like a postal service, accepting vesicles (tiny packages) and modifying proteins before shipping them off. Lysosomes are the cell's cleanup crew, packed with digestive enzymes that break down pathogens and cellular waste. Don't forget the mitochondria - these powerhouses run aerobic respiration to fuel everything the cell does.
Remember Eukaryotic ribosomes are 80s in size - this number will come up in your exams!
Prokaryotic cells include bacteria and archaea, and they've mastered the art of living simple. These unicellular organisms lack a true nucleus and membrane-bound organelles, but don't mistake simplicity for weakness - they've been thriving for billions of years.
Instead of a nucleus, prokaryotes keep their genetic material in a region called the nucleoid. This DNA is circular and looped, floating freely without being wrapped around histones like in eukaryotes. Their ribosomes are smaller too, measuring 70s instead of the 80s found in eukaryotic cells.
The cell wall made of peptidoglycan gives structure and protection, whilst the slimy capsule acts like a protective raincoat against dehydration and immune system attacks. Many prokaryotes have pili (tiny hairs) and flagella that rotate like propellers for movement.
Key Difference Prokaryotes = no true nucleus; Eukaryotes = true nucleus with membrane protection.
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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Explore the key differences between eukaryotic and prokaryotic cells, including animal, plant, and bacterial cell structures. This summary covers essential components such as the nucleus, cytoplasm, cell membrane, mitochondria, ribosomes, chloroplasts, cell wall, vacuoles, plasmid DNA, and flagella, along with their functions in cellular processes.
BiologyExplore the five main kingdoms of life, focusing on the characteristics of eukaryotic cells, including protists, fungi, and their classification. This summary covers key concepts such as multicellularity, heterotrophy, and autotrophy, providing a clear overview for students studying biological classification.
BiologyExplore the structure and function of key cell organelles in this detailed summary. Understand the roles of the nucleus, mitochondria, ribosomes, and more in cellular processes. Ideal for A-Level Biology students seeking to grasp essential concepts in cell biology.
BiologyExplore the essential components of cells and their functions in this detailed summary. Key topics include the nucleus, mitochondria, chloroplasts, Golgi apparatus, endoplasmic reticulum, lysosomes, ribosomes, and cell walls. Ideal for A-level Biology students, this resource provides clear explanations and diagrams to enhance understanding of cellular structures and processes.
BiologyExplore the intricate structures of eukaryotic cells, focusing on the nucleus, endoplasmic reticulum, and mitochondria. This summary covers key functions, including DNA replication, protein synthesis, and ATP production, essential for A-level biology students. Ideal for exam preparation and understanding cellular processes.
BiologyExplore the distinctions between prokaryotic and eukaryotic cells across the five kingdoms: Prokaryotae, Protoctista, Fungi, Plantae, and Animalia. This summary covers cellular structures, functions, and key characteristics, including ribosome types, DNA structure, and nutritional modes. Ideal for students studying cellular biology and taxonomy.
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
Gen J
@genj_nuom
Every living thing on Earth is made up of cells, but not all cells are created equal. Understanding the fundamental differences between eukaryotic and prokaryotic cells is crucial for grasping how life works at the cellular level.
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You'll find eukaryotic cells in animals, plants, fungi, and protists - basically everything you can see without a microscope. What makes these cells special is their sophisticated internal organisation that's like having different departments in a factory.
The most defining feature is the true nucleus, which acts as the cell's control centre. It's surrounded by a protective nuclear envelope with tiny gates called nuclear pores that control what goes in and out. Think of it as a high-security office where all the important genetic information is stored safely.
Membrane-bound organelles are what really set eukaryotic cells apart. The Smooth Endoplasmic Reticulum (Smooth ER) looks like a series of flattened pancakes and specialises in making steroids and lipids. Meanwhile, the Rough ER does the same job but has ribosomes stuck to its surface, making it look bumpy under a microscope.
Quick Tip: Remember that "eu" means "true" in Greek - so eukaryotes have a "true nucleus"!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
The Rough ER isn't just about looking bumpy - those attached ribosomes are protein-making machines. Once proteins are made, they fold into their proper 3D shapes inside the ER, like origami finding its final form.
Centrioles become the stars during cell division, producing spindle fibres that grab onto replicated chromosomes and pull them apart during mitosis. Inside the nucleus, the nucleolus works as the ribosome factory, constantly churning out these essential protein-makers.
The Golgi apparatus acts like a postal service, accepting vesicles (tiny packages) and modifying proteins before shipping them off. Lysosomes are the cell's cleanup crew, packed with digestive enzymes that break down pathogens and cellular waste. Don't forget the mitochondria - these powerhouses run aerobic respiration to fuel everything the cell does.
Remember: Eukaryotic ribosomes are 80s in size - this number will come up in your exams!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Prokaryotic cells include bacteria and archaea, and they've mastered the art of living simple. These unicellular organisms lack a true nucleus and membrane-bound organelles, but don't mistake simplicity for weakness - they've been thriving for billions of years.
Instead of a nucleus, prokaryotes keep their genetic material in a region called the nucleoid. This DNA is circular and looped, floating freely without being wrapped around histones like in eukaryotes. Their ribosomes are smaller too, measuring 70s instead of the 80s found in eukaryotic cells.
The cell wall made of peptidoglycan gives structure and protection, whilst the slimy capsule acts like a protective raincoat against dehydration and immune system attacks. Many prokaryotes have pili (tiny hairs) and flagella that rotate like propellers for movement.
Key Difference: Prokaryotes = no true nucleus; Eukaryotes = true nucleus with membrane protection.
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.
0
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the key differences between eukaryotic and prokaryotic cells, including animal, plant, and bacterial cell structures. This summary covers essential components such as the nucleus, cytoplasm, cell membrane, mitochondria, ribosomes, chloroplasts, cell wall, vacuoles, plasmid DNA, and flagella, along with their functions in cellular processes.
BiologyExplore the five main kingdoms of life, focusing on the characteristics of eukaryotic cells, including protists, fungi, and their classification. This summary covers key concepts such as multicellularity, heterotrophy, and autotrophy, providing a clear overview for students studying biological classification.
BiologyExplore the structure and function of key cell organelles in this detailed summary. Understand the roles of the nucleus, mitochondria, ribosomes, and more in cellular processes. Ideal for A-Level Biology students seeking to grasp essential concepts in cell biology.
BiologyExplore the essential components of cells and their functions in this detailed summary. Key topics include the nucleus, mitochondria, chloroplasts, Golgi apparatus, endoplasmic reticulum, lysosomes, ribosomes, and cell walls. Ideal for A-level Biology students, this resource provides clear explanations and diagrams to enhance understanding of cellular structures and processes.
BiologyExplore the intricate structures of eukaryotic cells, focusing on the nucleus, endoplasmic reticulum, and mitochondria. This summary covers key functions, including DNA replication, protein synthesis, and ATP production, essential for A-level biology students. Ideal for exam preparation and understanding cellular processes.
BiologyExplore the distinctions between prokaryotic and eukaryotic cells across the five kingdoms: Prokaryotae, Protoctista, Fungi, Plantae, and Animalia. This summary covers cellular structures, functions, and key characteristics, including ribosome types, DNA structure, and nutritional modes. Ideal for students studying cellular biology and taxonomy.
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