The document provides an in-depth overview of cell biology, focusing... Show more
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Subjects
Careers
Energy transfers (a2 only)
Infection and response
Homeostasis and response
Responding to change (a2 only)
Cell biology
Organisms respond to changes in their internal and external environments (a-level only)
Biological molecules
Organisation
Substance exchange
The control of gene expression (a2 only)
Bioenergetics
Genetic information & variation
Inheritance, variation and evolution
Ecology
Cells
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Medieval period: 1066 -1509
2m wars and welfare: britain in transition, 1906-1957
World war two & the holocaust
2o democracy and nazism: germany, 1918-1945
1l the quest for political stability: germany, 1871-1991
1f industrialisation and the people: britain, c1783-1885
Britain & the wider world: 1745 -1901
2d religious conflict and the church in england, c1529-c1570
The cold war
1c the tudors: england, 1485-1603
Inter-war germany
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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5
1
Unit 1: Cell Biology
19
•
10 Jul 2025
•
Nini Ju
@jiangyueju_wdwe
The document provides an in-depth overview of cell biology, focusing... Show more
This page delves deeper into the structures of bacterial and fungal cells, providing detailed diagrams and explanations of their unique features.
Bacterial cells are described as having a circular chromosome, plasmids, and a cell wall with a different chemical structure compared to plant and fungal cells. The absence of a nucleus and mitochondria in bacterial cells is noted as a key difference from other cell types.
Highlight: Bacterial cells lack a true nucleus and instead have a circular chromosome and plasmids containing their genetic material.
Fungal cells are shown to have similarities to both plant and animal cells, possessing a cell wall like plant cells but also containing mitochondria like animal cells. The irregular shape of fungal cells is highlighted as a distinguishing feature.
Example: Fungal cells have a cell wall like plant cells, but they also contain mitochondria similar to animal cells, making them unique among eukaryotic cells.
The page emphasizes that all cell types contain ribosomes, cell membranes, and cytoplasm, reinforcing the fundamental similarities across different cell types despite their structural differences.
This page focuses on the mechanisms of transport across cell membranes, explaining key concepts such as diffusion, active transport, and osmosis.
Diffusion is described as the passive movement of molecules from areas of high concentration to low concentration, requiring no energy. Active transport, in contrast, is explained as the movement of molecules against the concentration gradient, requiring energy and involving proteins in the cell membrane.
Definition: Osmosis is the diffusion of water molecules across a selectively permeable membrane from an area of high water concentration to an area of low water concentration.
The page details the molecules that can enter and exit cells through the membrane, such as oxygen and glucose entering, and carbon dioxide and urea exiting. It also explains that larger molecules like starch and proteins are too big to pass through membrane pores.
Example: Oxygen and glucose can enter cells through the membrane, while carbon dioxide and urea can exit. However, larger molecules like starch and proteins cannot pass through due to their size.
The effects of osmosis on plant and animal cells are described, introducing the concepts of turgid and plasmolysed cells. The page explains how plant cells can withstand water gain due to their cell walls, while animal cells may burst when they gain too much water.
Vocabulary: Turgid refers to a plant cell that has gained water and is swollen, while plasmolysed describes a plant cell that has lost water and has a shrunken cytoplasm.
This page provides an overview of the cell membrane structure and the functions of key cell organelles.
The cell membrane is described as being composed of phospholipids and proteins. Its role in controlling the diffusion of molecules in and out of the cell is emphasized, along with its selective permeability.
Highlight: The cell membrane is selectively permeable, controlling which molecules can enter or exit the cell.
The page introduces the functions of important cell organelles:
Definition: Mitochondria are organelles that serve as the main site of energy production through aerobic respiration in eukaryotic cells.
Vocabulary: Ribosomes are cellular structures responsible for protein synthesis, present in all cell types.
This information provides a concise summary of the key functions of these essential cellular components, tying together the concepts of cell structure and function discussed throughout the document.
This page provides a comprehensive comparison of plant, animal, fungal and bacterial cell structures. It highlights the key differences and similarities between these cell types.
Plant cells are characterized by the presence of a cell wall, large vacuole, and chloroplasts, which are absent in animal cells. The page includes detailed diagrams of plant and animal cells, labeling important organelles and structures.
Highlight: Plant cells have unique features like a cell wall, large vacuole, and chloroplasts that are not found in animal cells.
Vocabulary: Chloroplasts are organelles found in plant cells that are responsible for photosynthesis.
The page also introduces bacterial and fungal cell structures, noting their unique features such as plasmids in bacterial cells and the different chemical composition of cell walls in plant, fungal, and bacterial cells.
Definition: Plasmids are small, circular pieces of DNA found in bacterial cells that can replicate independently of the main chromosome.
Common structures found in all cell types, including ribosomes, cell membrane, and cytoplasm, are also highlighted, emphasizing the fundamental similarities across different cell types.
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.
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
Nini Ju
@jiangyueju_wdwe
The document provides an in-depth overview of cell biology, focusing on the differences between plant, animal, fungal and bacterial cells, cell membrane transport, and organelle functions. It covers key concepts in cell structure, membrane composition, and cellular processes essential... Show more
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page delves deeper into the structures of bacterial and fungal cells, providing detailed diagrams and explanations of their unique features.
Bacterial cells are described as having a circular chromosome, plasmids, and a cell wall with a different chemical structure compared to plant and fungal cells. The absence of a nucleus and mitochondria in bacterial cells is noted as a key difference from other cell types.
Highlight: Bacterial cells lack a true nucleus and instead have a circular chromosome and plasmids containing their genetic material.
Fungal cells are shown to have similarities to both plant and animal cells, possessing a cell wall like plant cells but also containing mitochondria like animal cells. The irregular shape of fungal cells is highlighted as a distinguishing feature.
Example: Fungal cells have a cell wall like plant cells, but they also contain mitochondria similar to animal cells, making them unique among eukaryotic cells.
The page emphasizes that all cell types contain ribosomes, cell membranes, and cytoplasm, reinforcing the fundamental similarities across different cell types despite their structural differences.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page focuses on the mechanisms of transport across cell membranes, explaining key concepts such as diffusion, active transport, and osmosis.
Diffusion is described as the passive movement of molecules from areas of high concentration to low concentration, requiring no energy. Active transport, in contrast, is explained as the movement of molecules against the concentration gradient, requiring energy and involving proteins in the cell membrane.
Definition: Osmosis is the diffusion of water molecules across a selectively permeable membrane from an area of high water concentration to an area of low water concentration.
The page details the molecules that can enter and exit cells through the membrane, such as oxygen and glucose entering, and carbon dioxide and urea exiting. It also explains that larger molecules like starch and proteins are too big to pass through membrane pores.
Example: Oxygen and glucose can enter cells through the membrane, while carbon dioxide and urea can exit. However, larger molecules like starch and proteins cannot pass through due to their size.
The effects of osmosis on plant and animal cells are described, introducing the concepts of turgid and plasmolysed cells. The page explains how plant cells can withstand water gain due to their cell walls, while animal cells may burst when they gain too much water.
Vocabulary: Turgid refers to a plant cell that has gained water and is swollen, while plasmolysed describes a plant cell that has lost water and has a shrunken cytoplasm.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page provides an overview of the cell membrane structure and the functions of key cell organelles.
The cell membrane is described as being composed of phospholipids and proteins. Its role in controlling the diffusion of molecules in and out of the cell is emphasized, along with its selective permeability.
Highlight: The cell membrane is selectively permeable, controlling which molecules can enter or exit the cell.
The page introduces the functions of important cell organelles:
Definition: Mitochondria are organelles that serve as the main site of energy production through aerobic respiration in eukaryotic cells.
Vocabulary: Ribosomes are cellular structures responsible for protein synthesis, present in all cell types.
This information provides a concise summary of the key functions of these essential cellular components, tying together the concepts of cell structure and function discussed throughout the document.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page provides a comprehensive comparison of plant, animal, fungal and bacterial cell structures. It highlights the key differences and similarities between these cell types.
Plant cells are characterized by the presence of a cell wall, large vacuole, and chloroplasts, which are absent in animal cells. The page includes detailed diagrams of plant and animal cells, labeling important organelles and structures.
Highlight: Plant cells have unique features like a cell wall, large vacuole, and chloroplasts that are not found in animal cells.
Vocabulary: Chloroplasts are organelles found in plant cells that are responsible for photosynthesis.
The page also introduces bacterial and fungal cell structures, noting their unique features such as plasmids in bacterial cells and the different chemical composition of cell walls in plant, fungal, and bacterial cells.
Definition: Plasmids are small, circular pieces of DNA found in bacterial cells that can replicate independently of the main chromosome.
Common structures found in all cell types, including ribosomes, cell membrane, and cytoplasm, are also highlighted, emphasizing the fundamental similarities across different cell types.
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.
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