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
Show all topics
Biology
10 Dec 2025
475
1 page
lexi thomas @lexithomas
Dive into the world of infections and how our bodies fight back! This unit explores various types of... Show more
Pathogens are micro-organisms that cause disease, coming in four main types. Bacteria are small cells that reproduce quickly and release toxins, while viruses are even smaller and live inside cells. Protists are carried by vectors like mosquitoes, and fungi spread through spores.
These pathogens spread in various ways including contaminated water, through the air we breathe, or by direct contact with infected surfaces. Your body has natural defenses like skin barriers, mucus, and cilia in your throat that work to keep pathogens out.
Plants can also get diseases! Look for signs like stunted growth, spotted leaves, or abnormal stems. Plants protect themselves with waxy cuticles, cell walls, and thorns. When they lack proper nutrients like nitrates or magnesium, they show specific symptoms like yellowing leaves.
Did you know? While antibiotics can effectively kill bacteria, they're completely useless against viruses because viruses live inside our cells where antibiotics can't reach them!
Viral diseases include measles (causing rashes and fever) and HIV (which attacks the immune system). Plants suffer from viruses too, like tobacco mosaic virus that discolours leaves and reduces photosynthesis.
Bacterial diseases like salmonella cause food poisoning with symptoms including fever and stomach cramps. Gonorrhoea is a sexually transmitted bacterial infection that can be treated with antibiotics.
Fungal and protist diseases affect both plants and humans. Rose black spot is a fungal disease treated with fungicides, while malaria is caused by a protist carried by mosquitoes.
Your immune system battles pathogens through phagocytosis - a process where white blood cells engulf invaders. Lymphocytes produce specific antibodies that bind to pathogens and immobilise them, while antitoxins neutralise harmful toxins.
Vaccination offers protection by introducing a weakened or dead version of a pathogen. This triggers your body to produce antibodies, preparing it for future infections. Other prevention methods include good hygiene, isolation, and vector control.
Medicine development follows a careful process testing on human cells, then animals, and finally human volunteers through clinical trials. Placebos and double-blind trials ensure results are reliable. Nature provides many valuable medicines too, like aspirin from willow trees and penicillin from mould.
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.
4
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore key concepts in disease prevention, including biological defenses, vaccination methods, and antibiotic use. This summary covers the immune system's response to pathogens, the role of vaccines in public health, and the importance of antibiotics in treating bacterial infections. Ideal for AQA GCSE Biology students seeking to understand the mechanisms of disease control and treatment.
BiologyExplore key concepts in infection and response, including the immune system, vaccination, and disease prevention. This comprehensive summary covers plant and human diseases, the role of pathogens, and the mechanisms of monoclonal antibodies. Ideal for AQA Biology students preparing for exams.
BiologyExplore the key types of plant pathogens, including viruses, bacteria, fungi, and protists. This summary covers their impact on plant health, symptoms of infection, and the role of essential nutrients like magnesium and nitrogen in plant growth. Ideal for GCSE Biology students studying Infection and Response.
BiologyComprehensive study notes covering key concepts in Infection and Response for GCSE AQA Biology. Explore topics such as antibiotics, viral and bacterial diseases, immune responses, and plant disease detection. Ideal for exam preparation and understanding disease prevention and treatment strategies.
BiologyExplore the mechanisms of infection and the immune response in this comprehensive overview. Learn about different types of pathogens, drug development, vaccination processes, and the role of monoclonal antibodies in treatment. This summary covers key concepts such as antibiotics, drug testing, and plant disease defenses, making it essential for biology students preparing for exams.
BiologyExplore key concepts from the Edexcel Triple Science Higher Biology Paper 1, including antibiotic treatment, cell division, genetic disorders, and reflex arcs. This summary covers essential topics and exam strategies to enhance your understanding and performance. Ideal for students preparing for their biology exams.
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
lexi thomas
@lexithomas
Dive into the world of infections and how our bodies fight back! This unit explores various types of disease-causing organisms, how they spread, and the fascinating ways our bodies and medical science combat them.
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Pathogens are micro-organisms that cause disease, coming in four main types. Bacteria are small cells that reproduce quickly and release toxins, while viruses are even smaller and live inside cells. Protists are carried by vectors like mosquitoes, and fungi spread through spores.
These pathogens spread in various ways including contaminated water, through the air we breathe, or by direct contact with infected surfaces. Your body has natural defenses like skin barriers, mucus, and cilia in your throat that work to keep pathogens out.
Plants can also get diseases! Look for signs like stunted growth, spotted leaves, or abnormal stems. Plants protect themselves with waxy cuticles, cell walls, and thorns. When they lack proper nutrients like nitrates or magnesium, they show specific symptoms like yellowing leaves.
Did you know? While antibiotics can effectively kill bacteria, they're completely useless against viruses because viruses live inside our cells where antibiotics can't reach them!
Viral diseases include measles (causing rashes and fever) and HIV (which attacks the immune system). Plants suffer from viruses too, like tobacco mosaic virus that discolours leaves and reduces photosynthesis.
Bacterial diseases like salmonella cause food poisoning with symptoms including fever and stomach cramps. Gonorrhoea is a sexually transmitted bacterial infection that can be treated with antibiotics.
Fungal and protist diseases affect both plants and humans. Rose black spot is a fungal disease treated with fungicides, while malaria is caused by a protist carried by mosquitoes.
Your immune system battles pathogens through phagocytosis - a process where white blood cells engulf invaders. Lymphocytes produce specific antibodies that bind to pathogens and immobilise them, while antitoxins neutralise harmful toxins.
Vaccination offers protection by introducing a weakened or dead version of a pathogen. This triggers your body to produce antibodies, preparing it for future infections. Other prevention methods include good hygiene, isolation, and vector control.
Medicine development follows a careful process: testing on human cells, then animals, and finally human volunteers through clinical trials. Placebos and double-blind trials ensure results are reliable. Nature provides many valuable medicines too, like aspirin from willow trees and penicillin from mould.
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.
4
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore key concepts in disease prevention, including biological defenses, vaccination methods, and antibiotic use. This summary covers the immune system's response to pathogens, the role of vaccines in public health, and the importance of antibiotics in treating bacterial infections. Ideal for AQA GCSE Biology students seeking to understand the mechanisms of disease control and treatment.
BiologyExplore key concepts in infection and response, including the immune system, vaccination, and disease prevention. This comprehensive summary covers plant and human diseases, the role of pathogens, and the mechanisms of monoclonal antibodies. Ideal for AQA Biology students preparing for exams.
BiologyExplore the key types of plant pathogens, including viruses, bacteria, fungi, and protists. This summary covers their impact on plant health, symptoms of infection, and the role of essential nutrients like magnesium and nitrogen in plant growth. Ideal for GCSE Biology students studying Infection and Response.
BiologyComprehensive study notes covering key concepts in Infection and Response for GCSE AQA Biology. Explore topics such as antibiotics, viral and bacterial diseases, immune responses, and plant disease detection. Ideal for exam preparation and understanding disease prevention and treatment strategies.
BiologyExplore the mechanisms of infection and the immune response in this comprehensive overview. Learn about different types of pathogens, drug development, vaccination processes, and the role of monoclonal antibodies in treatment. This summary covers key concepts such as antibiotics, drug testing, and plant disease defenses, making it essential for biology students preparing for exams.
BiologyExplore key concepts from the Edexcel Triple Science Higher Biology Paper 1, including antibiotic treatment, cell division, genetic disorders, and reflex arcs. This summary covers essential topics and exam strategies to enhance your understanding and performance. Ideal for students preparing for their biology exams.
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