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
1l the quest for political stability: germany, 1871-1991
Britain & the wider world: 1745 -1901
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
3 Dec 2025
69
7 pages
Lily Browne @lilybrowne_dqkk
This comprehensive guide covers key concepts in biology, focusing on food webs, food chains, and ecological relationships. It... Show more
This page discusses habitats and introduces the concept of ecological pyramids, specifically the pyramid of numbers and biomass in ecology.
Habitats are environments where specific organisms can grow and thrive. They provide all the necessary elements for survival, including appropriate light, oxygen, and water levels.
Definition A habitat is an environment that provides the conditions necessary for an organism to survive and reproduce.
Key factors in habitats include
The pyramid of numbers represents the quantity of organisms at each trophic level in a food chain. Each bar in the pyramid shows the number of individuals at that feeding level.
Example In a simple food chain, one sparrowhawk might feed on 5 bluetits, which in turn feed on 10 caterpillars.
This page continues the discussion on ecological pyramids, focusing on the pyramid of biomass and energy flow in ecosystems.
Definition Biomass is the total mass of living material in each organism multiplied by the number of organisms at that trophic level.
The pyramid of biomass represents the total biomass at each trophic level in an ecosystem. It provides a more accurate representation of energy distribution than the pyramid of numbers.
Example In an ecosystem with one sparrowhawk, 5 bluetits, 10 caterpillars, and 30 oak trees, the biomass pyramid would show increasing mass from top to bottom.
Highlight As you move up the food chain, energy is lost at each trophic level due to inefficient energy transfer and heat loss.
This page introduces the concepts of bioaccumulation and biomagnification in food chains, along with the equation for photosynthesis and the seven life processes.
Definition Bioaccumulation is the process of substances, such as toxic chemicals, accumulating in living organisms at a rate faster than they are metabolized or excreted.
Definition Biomagnification is the process of increasing concentration of a substance in the tissues of organisms at successively higher levels in the food chain.
The difference between bioaccumulation and biomagnification in food chains is that bioaccumulation occurs within an organism, while biomagnification occurs across trophic levels.
Example Bioaccumulation and biomagnification in food chains examples include the concentration of DDT in fish-eating birds or mercury in large predatory fish.
Photosynthesis equation Carbon dioxide + water → glucose + oxygen
The seven life processes (MRS GREN)
This page discusses the organization of living organisms, focusing on tissues and organs.
Definition A tissue is the second level of organization in living organisms, consisting of a group of similar cells working together to perform a specific function.
Example Muscle tissue is an example of animal tissue.
Definition An organ is the third level of organization, composed of different tissues working together to perform specific functions.
Examples of organs include
This page focuses on cells, the fundamental units of life, and their structures in both animal and plant cells.
Definition Cells are the basic structural and functional units of all living organisms.
Organisms can be
Key components of animal cells
Additional components in plant cells
This page details the functions of various cell structures and introduces the concept of specialized cells.
Functions of cell structures
Definition Specialized cells are cells that perform specific functions in multicellular organisms.
Examples of specialized cells
Highlight Specialized cells have unique structures that allow them to perform their specific functions efficiently.
This page introduces the concepts of food webs and food chains, providing instructions on how to draw a food web and food chain for kids. Food chains represent simple linear feeding relationships, while food webs show more complex interactions between multiple species.
Definition A food chain is a linear sequence of organisms showing who eats whom, while a food web is a more complex diagram showing multiple feeding relationships within an ecosystem.
How to draw a food chain step by step
How to draw a food web and food chain with pencil
Highlight Remember that arrows in food webs and chains show the direction of energy transfer from prey to predator.
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.
10
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore 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 cell biology, including eukaryotic and prokaryotic cells, organelles, and tissue types. This summary covers the nucleus, mitochondria, chloroplasts, and various tissue types, providing a comprehensive overview for AS Level Biology students. Ideal for exam preparation and understanding cellular processes.
BiologyExplore the key differences and similarities between animal and plant cells, including their unique subcellular structures such as the cell wall, chloroplasts, and organelles like mitochondria and ribosomes. This summary provides a clear overview of cellular functions and shapes, essential for understanding basic biology concepts.
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
Lily Browne
@lilybrowne_dqkk
This comprehensive guide covers key concepts in biology, focusing on food webs, food chains, and ecological relationships. It provides detailed explanations and examples to help young students understand these important topics.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page discusses habitats and introduces the concept of ecological pyramids, specifically the pyramid of numbers and biomass in ecology.
Habitats are environments where specific organisms can grow and thrive. They provide all the necessary elements for survival, including appropriate light, oxygen, and water levels.
Definition: A habitat is an environment that provides the conditions necessary for an organism to survive and reproduce.
Key factors in habitats include:
The pyramid of numbers represents the quantity of organisms at each trophic level in a food chain. Each bar in the pyramid shows the number of individuals at that feeding level.
Example: In a simple food chain, one sparrowhawk might feed on 5 bluetits, which in turn feed on 10 caterpillars.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page continues the discussion on ecological pyramids, focusing on the pyramid of biomass and energy flow in ecosystems.
Definition: Biomass is the total mass of living material in each organism multiplied by the number of organisms at that trophic level.
The pyramid of biomass represents the total biomass at each trophic level in an ecosystem. It provides a more accurate representation of energy distribution than the pyramid of numbers.
Example: In an ecosystem with one sparrowhawk, 5 bluetits, 10 caterpillars, and 30 oak trees, the biomass pyramid would show increasing mass from top to bottom.
Highlight: As you move up the food chain, energy is lost at each trophic level due to inefficient energy transfer and heat loss.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page introduces the concepts of bioaccumulation and biomagnification in food chains, along with the equation for photosynthesis and the seven life processes.
Definition: Bioaccumulation is the process of substances, such as toxic chemicals, accumulating in living organisms at a rate faster than they are metabolized or excreted.
Definition: Biomagnification is the process of increasing concentration of a substance in the tissues of organisms at successively higher levels in the food chain.
The difference between bioaccumulation and biomagnification in food chains is that bioaccumulation occurs within an organism, while biomagnification occurs across trophic levels.
Example: Bioaccumulation and biomagnification in food chains examples include the concentration of DDT in fish-eating birds or mercury in large predatory fish.
Photosynthesis equation: Carbon dioxide + water → glucose + oxygen
The seven life processes (MRS GREN):
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page discusses the organization of living organisms, focusing on tissues and organs.
Definition: A tissue is the second level of organization in living organisms, consisting of a group of similar cells working together to perform a specific function.
Example: Muscle tissue is an example of animal tissue.
Definition: An organ is the third level of organization, composed of different tissues working together to perform specific functions.
Examples of organs include:
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page focuses on cells, the fundamental units of life, and their structures in both animal and plant cells.
Definition: Cells are the basic structural and functional units of all living organisms.
Organisms can be:
Key components of animal cells:
Additional components in plant cells:
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page details the functions of various cell structures and introduces the concept of specialized cells.
Functions of cell structures:
Definition: Specialized cells are cells that perform specific functions in multicellular organisms.
Examples of specialized cells:
Highlight: Specialized cells have unique structures that allow them to perform their specific functions efficiently.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page introduces the concepts of food webs and food chains, providing instructions on how to draw a food web and food chain for kids. Food chains represent simple linear feeding relationships, while food webs show more complex interactions between multiple species.
Definition: A food chain is a linear sequence of organisms showing who eats whom, while a food web is a more complex diagram showing multiple feeding relationships within an ecosystem.
How to draw a food chain step by step:
How to draw a food web and food chain with pencil:
Highlight: Remember that arrows in food webs and chains show the direction of energy transfer from prey to predator.
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.
10
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore 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 cell biology, including eukaryotic and prokaryotic cells, organelles, and tissue types. This summary covers the nucleus, mitochondria, chloroplasts, and various tissue types, providing a comprehensive overview for AS Level Biology students. Ideal for exam preparation and understanding cellular processes.
BiologyExplore the key differences and similarities between animal and plant cells, including their unique subcellular structures such as the cell wall, chloroplasts, and organelles like mitochondria and ribosomes. This summary provides a clear overview of cellular functions and shapes, essential for understanding basic biology concepts.
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
