Ecology is all about understanding how living things interact with... Show more
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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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36
0
Emily Birks
09/12/2025
Biology
Ecology - Triple Science/Combined - Higher Tier
1,408
•
9 Dec 2025
•
Emily Birks
@emilybirks_faby
Ecology is all about understanding how living things interact with... Show more

Ever wondered how all living things are connected? It starts with understanding the basic building blocks of nature. A population is simply all the members of one species living in the same area, whilst a habitat is where they actually live. When different populations come together, they form a community.
An ecosystem takes this further - it's the complete picture showing how living things (biotic factors) interact with non-living things (abiotic factors). Abiotic factors include temperature, light, and soil pH, whilst biotic factors cover predators, competition for mates, and human interference.
Food chains show you exactly how energy moves through ecosystems. They start with producers (plants that capture sunlight), then move through primary consumers (herbivores), secondary consumers (carnivores), and finally tertiary consumers (apex predators). The arrows always point in the direction that biomass is transferred.
Remember: Only about 1% of light energy actually gets converted into biomass by plants through photosynthesis!
Here's where it gets interesting - energy transfers aren't perfect. Organisms lose energy through waste, breathing, and producing inedible parts like bones. You can calculate efficiency using: (energy transferred ÷ total energy available) × 100.

The carbon cycle and water cycle are like nature's recycling systems, and they're absolutely crucial for life. In the carbon cycle, plants absorb CO₂ during photosynthesis, animals eat plants (transferring carbon), and both release CO₂ back through respiration. Burning fossil fuels also pumps CO₂ into the atmosphere.
Decomposition is where bacteria and fungi break down dead material, releasing carbon back to the environment. This happens in two ways: aerobic (with oxygen) which is efficient, or anaerobic (without oxygen) which produces less energy but can occur underwater or in soil.
The water cycle keeps everything hydrated - water evaporates from oceans and lakes, condenses into clouds, falls as precipitation, then flows back to water bodies. Simple but essential!
Unfortunately, human activities are disrupting these natural systems. We're releasing greenhouse gases (water vapour, CO₂, methane, nitrous oxide, and CFCs), causing global warming and habitat destruction. Pollution affects water sources, and changing climates force animals to migrate.
Key Point: Understanding these cycles helps explain why environmental protection matters so much!
Scientists measure ecosystem health using quadrats (0.25m² frames for counting organisms) and transects (lines across habitats). You can estimate total populations using: number counted × (total area ÷ area sampled).
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.
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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
Emily Birks
@emilybirks_faby
Ecology is all about understanding how living things interact with each other and their environment. You'll discover the fascinating connections between organisms, energy flow, and the natural cycles that keep our planet running smoothly.

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Ever wondered how all living things are connected? It starts with understanding the basic building blocks of nature. A population is simply all the members of one species living in the same area, whilst a habitat is where they actually live. When different populations come together, they form a community.
An ecosystem takes this further - it's the complete picture showing how living things (biotic factors) interact with non-living things (abiotic factors). Abiotic factors include temperature, light, and soil pH, whilst biotic factors cover predators, competition for mates, and human interference.
Food chains show you exactly how energy moves through ecosystems. They start with producers (plants that capture sunlight), then move through primary consumers (herbivores), secondary consumers (carnivores), and finally tertiary consumers (apex predators). The arrows always point in the direction that biomass is transferred.
Remember: Only about 1% of light energy actually gets converted into biomass by plants through photosynthesis!
Here's where it gets interesting - energy transfers aren't perfect. Organisms lose energy through waste, breathing, and producing inedible parts like bones. You can calculate efficiency using: (energy transferred ÷ total energy available) × 100.

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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
The carbon cycle and water cycle are like nature's recycling systems, and they're absolutely crucial for life. In the carbon cycle, plants absorb CO₂ during photosynthesis, animals eat plants (transferring carbon), and both release CO₂ back through respiration. Burning fossil fuels also pumps CO₂ into the atmosphere.
Decomposition is where bacteria and fungi break down dead material, releasing carbon back to the environment. This happens in two ways: aerobic (with oxygen) which is efficient, or anaerobic (without oxygen) which produces less energy but can occur underwater or in soil.
The water cycle keeps everything hydrated - water evaporates from oceans and lakes, condenses into clouds, falls as precipitation, then flows back to water bodies. Simple but essential!
Unfortunately, human activities are disrupting these natural systems. We're releasing greenhouse gases (water vapour, CO₂, methane, nitrous oxide, and CFCs), causing global warming and habitat destruction. Pollution affects water sources, and changing climates force animals to migrate.
Key Point: Understanding these cycles helps explain why environmental protection matters so much!
Scientists measure ecosystem health using quadrats (0.25m² frames for counting organisms) and transects (lines across habitats). You can estimate total populations using: number counted × (total area ÷ area sampled).
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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function of the digestive system parts
Explore the intricate processes of photosynthesis, including light-dependent and light-independent reactions, chloroplast structure, and the role of pigments like chlorophyll. This summary covers key concepts such as thylakoids, the Calvin cycle, and the action spectrum, providing a comprehensive overview for A-level Biology students.
Explore the Calvin Cycle, the light-independent reactions of photosynthesis occurring in the stroma. This summary covers the journey of carbon dioxide, the role of RuBISCO, ATP and NADPH in synthesizing glucose, and the regeneration of RuBP. Ideal for students studying photosynthesis and its biochemical processes.
Explore the key processes of cellular respiration, including glycolysis, the Krebs cycle, and oxidative phosphorylation. This summary highlights ATP production, metabolic pathways, and the role of NADH and FADH2 in energy transfer. Ideal for A2 Level WJEC biology students.
Explore the impact of temperature on enzyme activity in this practical guide. Learn to conduct experiments using trypsin and milk powder to measure reaction rates, understand enzyme kinetics, and evaluate safety protocols. Ideal for A-Level Biology students, this resource covers essential techniques, risk assessments, and data analysis methods.
Explore the intricate processes of photosynthesis, focusing on the light-dependent and light-independent reactions. This summary covers key concepts such as chloroplast structure, the role of chlorophyll, photolysis, ATP production, and the Calvin cycle. Ideal for A Level Biology students seeking a comprehensive understanding of photosynthesis.
App 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