Maths
Chemistry
Biology
English Language
History
Responding to change (a2 only)
Infection and response
Homeostasis and response
Energy transfers (a2 only)
Cell biology
Organisms respond to changes in their internal and external environments (a-level only)
Biological molecules
Organisation
Substance exchange
Bioenergetics
Genetic information & variation
Inheritance, variation and evolution
Genetics & ecosystems (a2 only)
Ecology
Cells
Show all topics
Britain & the wider world: 1745 -1901
1l the quest for political stability: germany, 1871-1991
The cold war
Inter-war germany
Medieval period: 1066 -1509
2d religious conflict and the church in england, c1529-c1570
2o democracy and nazism: germany, 1918-1945
1f industrialisation and the people: britain, c1783-1885
1c the tudors: england, 1485-1603
2m wars and welfare: britain in transition, 1906-1957
World war two & the holocaust
2n revolution and dictatorship: russia, 1917-1953
2s the making of modern britain, 1951-2007
World war one
Britain: 1509 -1745
Show all topics
Biology
30 Nov 2025
47
2 pages
The Science Guy @thegcsescienceguy
Your body is like a massive construction project where cells are the basic building blocks that create everything... Show more
Think of cells as tiny LEGO bricks - they're the basic building blocks of all living things. Just like how LEGO bricks connect to make bigger structures, cells group together to form tissues (like muscle tissue), which then combine to create organs (like your heart), and organs work together in organ systems (like your digestive system).
Enzymes are your body's speed demons - they're biological catalysts that massively speed up chemical reactions. Without them, the chemical reactions in your body would happen so slowly you'd literally be dead! They work by providing a special docking station called an active site where substrates (the starting materials) can transform into products.
Here's the clever bit enzymes don't get used up in the reaction. They're like a really efficient factory worker who can keep doing the same job over and over again without getting tired.
Remember this Enzymes are super picky about temperature and pH. Too hot, too cold, or wrong acidity levels will change the shape of their active site, making them completely useless!
Your digestion system uses three main enzyme superstars to break down your food into molecules small enough to actually use. Amylase attacks carbohydrates like bread and pasta, breaking starch down into smaller sugars - you can find it working in your mouth (saliva) and small intestine.
Protease is the protein destroyer, chopping up meat and beans into amino acids in your stomach and small intestine. Meanwhile, lipase tackles fats and oils, splitting them into glycerol and fatty acids in your small intestine.
Bile is like the ultimate wingman for digestion, even though it's not technically an enzyme. Made in your liver and stored in your gall bladder, bile does two brilliant jobs it makes your small intestine more alkaline (so enzymes work better) and breaks fat into tiny droplets, giving lipase a much bigger surface area to work on.
Top tip These broken-down products (sugars, amino acids, glycerol, and fatty acids) can be rebuilt into new carbohydrates, proteins, and lipids that your body actually needs!
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.
1
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the intricate workings of biological systems, including the circulatory and digestive systems. This summary covers key concepts such as heart structure, blood components, enzyme functions, and the role of digestive enzymes in nutrient absorption. Ideal for students seeking a comprehensive understanding of biology organization.
BiologyExplore the role of digestive enzymes in breaking down food into absorbable molecules. This summary covers key enzymes like amylase, protease, and lipase, their sites of production (salivary glands, pancreas, small intestine), and the reactions they catalyze. Ideal for students studying biology and human digestion.
BiologyExplore key concepts of the digestive system and enzyme functions with this comprehensive recap. Learn about bile's role, enzyme specificity, and biological tests for sugars, starch, and proteins. Ideal for quick revision and exam preparation.
BiologyExplore the intricate roles of enzymes and the digestive system in human physiology. This summary covers key concepts such as protein structure, enzyme function, metabolic reactions, and the digestion of carbohydrates, proteins, and lipids. Understand how enzymes act as biological catalysts and the importance of pH and temperature in enzyme activity. Ideal for AQA B3 curriculum.
BiologyExplore the intricate process of human digestion, from the mouth to the large intestine. This summary covers key concepts such as digestive enzymes, nutrient absorption, and the roles of various organs in the digestive system. Ideal for GCSE biology students seeking a clear understanding of how food is processed in the body.
BiologyExplore the role of enzymes as biological catalysts in digestion, including the lock and key model, factors affecting enzyme activity, and the digestive process. This summary covers key concepts such as enzyme-substrate complexes, optimal conditions for enzyme function, and the digestive system's organization. Ideal for AQA GCSE Biology revision.
BiologyApp Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The Science Guy
@thegcsescienceguy
Your body is like a massive construction project where cells are the basic building blocks that create everything from your muscles to your brain. Understanding how cells work together and how enzymes speed up chemical reactions will help you grasp... Show more
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Think of cells as tiny LEGO bricks - they're the basic building blocks of all living things. Just like how LEGO bricks connect to make bigger structures, cells group together to form tissues (like muscle tissue), which then combine to create organs (like your heart), and organs work together in organ systems (like your digestive system).
Enzymes are your body's speed demons - they're biological catalysts that massively speed up chemical reactions. Without them, the chemical reactions in your body would happen so slowly you'd literally be dead! They work by providing a special docking station called an active site where substrates (the starting materials) can transform into products.
Here's the clever bit: enzymes don't get used up in the reaction. They're like a really efficient factory worker who can keep doing the same job over and over again without getting tired.
Remember this: Enzymes are super picky about temperature and pH. Too hot, too cold, or wrong acidity levels will change the shape of their active site, making them completely useless!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Your digestion system uses three main enzyme superstars to break down your food into molecules small enough to actually use. Amylase attacks carbohydrates like bread and pasta, breaking starch down into smaller sugars - you can find it working in your mouth (saliva) and small intestine.
Protease is the protein destroyer, chopping up meat and beans into amino acids in your stomach and small intestine. Meanwhile, lipase tackles fats and oils, splitting them into glycerol and fatty acids in your small intestine.
Bile is like the ultimate wingman for digestion, even though it's not technically an enzyme. Made in your liver and stored in your gall bladder, bile does two brilliant jobs: it makes your small intestine more alkaline (so enzymes work better) and breaks fat into tiny droplets, giving lipase a much bigger surface area to work on.
Top tip: These broken-down products (sugars, amino acids, glycerol, and fatty acids) can be rebuilt into new carbohydrates, proteins, and lipids that your body actually needs!
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.
1
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the intricate workings of biological systems, including the circulatory and digestive systems. This summary covers key concepts such as heart structure, blood components, enzyme functions, and the role of digestive enzymes in nutrient absorption. Ideal for students seeking a comprehensive understanding of biology organization.
BiologyExplore the role of digestive enzymes in breaking down food into absorbable molecules. This summary covers key enzymes like amylase, protease, and lipase, their sites of production (salivary glands, pancreas, small intestine), and the reactions they catalyze. Ideal for students studying biology and human digestion.
BiologyExplore key concepts of the digestive system and enzyme functions with this comprehensive recap. Learn about bile's role, enzyme specificity, and biological tests for sugars, starch, and proteins. Ideal for quick revision and exam preparation.
BiologyExplore the intricate roles of enzymes and the digestive system in human physiology. This summary covers key concepts such as protein structure, enzyme function, metabolic reactions, and the digestion of carbohydrates, proteins, and lipids. Understand how enzymes act as biological catalysts and the importance of pH and temperature in enzyme activity. Ideal for AQA B3 curriculum.
BiologyExplore the intricate process of human digestion, from the mouth to the large intestine. This summary covers key concepts such as digestive enzymes, nutrient absorption, and the roles of various organs in the digestive system. Ideal for GCSE biology students seeking a clear understanding of how food is processed in the body.
BiologyExplore the role of enzymes as biological catalysts in digestion, including the lock and key model, factors affecting enzyme activity, and the digestive process. This summary covers key concepts such as enzyme-substrate complexes, optimal conditions for enzyme function, and the digestive system's organization. Ideal for AQA GCSE Biology revision.
BiologyApp Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
Biología
Sociology