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
1 Dec 2025
214
2 pages
k๐ซถ @notesfromtheheart
Your body contains trillions of cells, but they're not all the same - and understanding why is crucial... Show more
Think of your body as having two main types of cells with completely different jobs. Somatic cells are basically every cell in your body except those involved in making babies - your skin, muscle, brain cells, the lot. These cells use mitosis to create identical copies of themselves when you need to grow or repair damage.
Germline cells are the special ones involved in reproduction. This includes your actual gametes (sperm and eggs) plus the stem cells that create them. Here's where it gets interesting - germline cells can divide in two ways mitosis to make more germline cells, or meiosis to create gametes.
Meiosis happens in two stages that are dead important to remember. First division separates homologous chromosomes, then the second division separates chromatids. This process reduces chromosome number by half, which is why gametes are haploid.
Quick Tip Remember that somatic = body cells, germline = reproductive cells. This distinction comes up constantly in exams!
Ever wondered how a single fertilised egg becomes a complex human with hundreds of different cell types? Cellular differentiation is your answer - it's when unspecialised cells become specialists by switching specific genes on and off. Once a cell differentiates, it only expresses proteins needed for its particular job.
Stem cells are the ultimate multitaskers because they can both reproduce themselves and differentiate into other cell types. Embryonic stem cells are the gold standard - they're pluripotent, meaning they can become any body cell because all their genes can potentially be switched on.
Tissue stem cells are more limited - they're multipotent and can only differentiate into cell types found in their specific tissue. This happens because some genes are already permanently switched off, restricting their potential.
These cells have massive therapeutic uses for repairing damaged organs and tissues. In research, they help scientists understand cell processes and can self-renew in lab conditions, making them perfect model cells for experiments.
Ethics Alert Using embryonic stem cells means destroying an embryo, which raises significant ethical questions you'll need to consider in discussions and essays.
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 โ all at your fingertips.
5
Smart Tools NEW
Transform this note into: โ 50+ Practice Questions โ Interactive Flashcards โ Full Mock Exam โ Essay Outlines
Explore the intricate structure and lifecycle of viruses in this detailed mindmap. Understand key concepts such as viral replication, infection stages, and the role of genetic material. Ideal for AQA A-level Biology students seeking to grasp the fundamentals of virology.
BiologyExplore the essential processes of protein synthesis, including transcription and translation. This summary covers the roles of mRNA and tRNA, the conversion of DNA to mRNA, and how amino acids are assembled into proteins. Ideal for Grade 5-9 students seeking to understand genetic coding and protein formation.
BiologyExplore key concepts in molecular biology, including DNA and RNA structure, transcription, translation, and protein synthesis. This summary covers essential topics such as mutations, stem cells, and the processes of cellular differentiation and gene expression. Ideal for students preparing for exams or seeking a comprehensive overview of Unit 1 in higher human biology.
BiologyExplore the essential functions of nucleic acids, including DNA and RNA structures, nucleotide composition, ATP's role in energy transfer, and the semi-conservative replication process. This summary also covers the Meselson-Stahl experiment and the genetic code, making it a vital resource for AS Level Biology students.
BiologyExplore the intricate mechanisms of gene regulation, including operons, transcription factors, and mutations. This summary covers key concepts such as the lac operon, transcriptional control, and post-transcriptional modifications, essential for understanding cellular control in biology. Ideal for OCR A Level Biology students.
BiologyExplore the essential processes of protein synthesis, including transcription and translation. This study note covers the roles of mRNA, tRNA, exons, and introns, detailing how genes are expressed to form proteins. Understand the significance of start and stop codons, RNA splicing, and the formation of peptide bonds. Ideal for higher biology students studying gene expression and regulation.
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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
k๐ซถ
@notesfromtheheart
Your body contains trillions of cells, but they're not all the same - and understanding why is crucial for grasping everything from growth to cancer treatment. This unit explores how cells specialise, reproduce, and sometimes go wrong, giving you the... Show more
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Think of your body as having two main types of cells with completely different jobs. Somatic cells are basically every cell in your body except those involved in making babies - your skin, muscle, brain cells, the lot. These cells use mitosis to create identical copies of themselves when you need to grow or repair damage.
Germline cells are the special ones involved in reproduction. This includes your actual gametes (sperm and eggs) plus the stem cells that create them. Here's where it gets interesting - germline cells can divide in two ways: mitosis to make more germline cells, or meiosis to create gametes.
Meiosis happens in two stages that are dead important to remember. First division separates homologous chromosomes, then the second division separates chromatids. This process reduces chromosome number by half, which is why gametes are haploid.
Quick Tip: Remember that somatic = body cells, germline = reproductive cells. This distinction comes up constantly in exams!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Ever wondered how a single fertilised egg becomes a complex human with hundreds of different cell types? Cellular differentiation is your answer - it's when unspecialised cells become specialists by switching specific genes on and off. Once a cell differentiates, it only expresses proteins needed for its particular job.
Stem cells are the ultimate multitaskers because they can both reproduce themselves and differentiate into other cell types. Embryonic stem cells are the gold standard - they're pluripotent, meaning they can become any body cell because all their genes can potentially be switched on.
Tissue stem cells are more limited - they're multipotent and can only differentiate into cell types found in their specific tissue. This happens because some genes are already permanently switched off, restricting their potential.
These cells have massive therapeutic uses for repairing damaged organs and tissues. In research, they help scientists understand cell processes and can self-renew in lab conditions, making them perfect model cells for experiments.
Ethics Alert: Using embryonic stem cells means destroying an embryo, which raises significant ethical questions you'll need to consider in discussions and essays.
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 โ all at your fingertips.
5
Smart Tools NEW
Transform this note into: โ 50+ Practice Questions โ Interactive Flashcards โ Full Mock Exam โ Essay Outlines
Explore the intricate structure and lifecycle of viruses in this detailed mindmap. Understand key concepts such as viral replication, infection stages, and the role of genetic material. Ideal for AQA A-level Biology students seeking to grasp the fundamentals of virology.
BiologyExplore the essential processes of protein synthesis, including transcription and translation. This summary covers the roles of mRNA and tRNA, the conversion of DNA to mRNA, and how amino acids are assembled into proteins. Ideal for Grade 5-9 students seeking to understand genetic coding and protein formation.
BiologyExplore key concepts in molecular biology, including DNA and RNA structure, transcription, translation, and protein synthesis. This summary covers essential topics such as mutations, stem cells, and the processes of cellular differentiation and gene expression. Ideal for students preparing for exams or seeking a comprehensive overview of Unit 1 in higher human biology.
BiologyExplore the essential functions of nucleic acids, including DNA and RNA structures, nucleotide composition, ATP's role in energy transfer, and the semi-conservative replication process. This summary also covers the Meselson-Stahl experiment and the genetic code, making it a vital resource for AS Level Biology students.
BiologyExplore the intricate mechanisms of gene regulation, including operons, transcription factors, and mutations. This summary covers key concepts such as the lac operon, transcriptional control, and post-transcriptional modifications, essential for understanding cellular control in biology. Ideal for OCR A Level Biology students.
BiologyExplore the essential processes of protein synthesis, including transcription and translation. This study note covers the roles of mRNA, tRNA, exons, and introns, detailing how genes are expressed to form proteins. Understand the significance of start and stop codons, RNA splicing, and the formation of peptide bonds. Ideal for higher biology students studying gene expression and regulation.
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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 itโs 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 didnโt even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโm 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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
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
