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0
E
eva marshall
03/12/2025
Biology
ccea gcse unit 1 higher tier biology
321
•
3 Dec 2025
•
CCEA GCSE Biology Unit 1 Higher Tier - Explore Cells
E
eva marshall
@evamarshall_
1 / 4
Cell Parts and Their Jobs
Think of a cell as a tiny factory where each part has a specific job to keep everything running smoothly. The cell membrane acts like a security guard, deciding what can enter and leave the cell - it's semi-permeable, meaning it's picky about what gets through.
Inside, the cytoplasm is where all the action happens - it's the liquid space where chemical reactions take place. The nucleus is like the cell's control centre, storing all your genetic information on chromosomes that you inherited from your parents.
Mitochondria are the powerhouses that release energy through aerobic respiration - basically, they keep your cells energised! Plant cells have extra bits: a cell wall made of cellulose for protection, chloroplasts containing chlorophyll to trap light for photosynthesis, and a large vacuole for support.
Quick Tip: Remember that plant cells have everything animal cells have, plus three extras: cell wall, chloroplasts, and a large vacuole!
From Cells to You - The Big Picture
Cells are just the beginning of an amazing organisational system that builds up to create you! When similar cells group together to do the same job, they form tissues - like cardiac muscle tissue in your heart.
Different tissues then team up to create organs with specific functions. Your heart, for example, combines muscle tissue, nerve tissue, and blood vessels to pump blood around your body.
Organ systems form when multiple organs work together - your circulatory system includes your heart, blood vessels, and blood all cooperating. Finally, all your organ systems work together to create a complete organism - that's you!
Remember: It's like Russian dolls - cells fit into tissues, tissues into organs, organs into systems, and systems make you!
How Stuff Gets Around - Diffusion
Diffusion is simply the movement of molecules from where there's loads of them to where there's fewer - like how perfume spreads across a room. This process is crucial for getting oxygen, water, and glucose into cells, and removing waste like CO₂.
Three main factors affect how fast diffusion happens. Temperature speeds things up because particles have more kinetic energy to move around. A larger surface area of the cell membrane means more particles can cross at once.
The concentration gradient is probably the most important factor - the bigger the difference between high and low concentration areas, the faster diffusion occurs. It's like water flowing down a steep hill versus a gentle slope.
Resolution in microscopy refers to seeing two separate points as distinct after magnification - basically, how clear and detailed your view is when studying cells.
Pro Tip: Think of diffusion like people leaving a crowded concert - they naturally spread out from the packed venue to less crowded areas!
Three Types of Cells You Need to Know
Animal cells contain the basic kit: cell membrane, mitochondria, cytoplasm, nucleus, and nuclear membrane. They're like the standard model that does all the essential life functions.
Plant cells have everything animal cells do, plus their special extras for plant life. The cell wall provides extra protection, chloroplasts enable photosynthesis, and the large vacuole helps maintain structure and support.
Bacterial cells are the rebels - they're much simpler with a non-cellulose cell wall, cytoplasm, and genetic material floating freely as loops of DNA rather than organised in a nucleus. They also have plasmids, which are small rings of extra DNA.
Stem cells are the ultimate multitaskers - they can divide and differentiate into specialised cells. Adult stem cells (found in bone marrow) are limited in what they can become, whilst embryonic stem cells can potentially become any type of cell.
Key Point: The main difference between these cell types is complexity - bacterial cells are simplest, animal cells are more complex, and plant cells are the most complex with extra features!
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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
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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
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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
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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
CCEA GCSE Biology Unit 1 Higher Tier - Explore Cells
E
eva marshall
@evamarshall_
Every living thing around you is made up of tiny building blocks called cells - from the skin on your hands to the leaves on trees. Understanding how cells work and organise themselves is key to grasping how all life... Show more
Cell Parts and Their Jobs
Think of a cell as a tiny factory where each part has a specific job to keep everything running smoothly. The cell membrane acts like a security guard, deciding what can enter and leave the cell - it's semi-permeable, meaning it's picky about what gets through.
Inside, the cytoplasm is where all the action happens - it's the liquid space where chemical reactions take place. The nucleus is like the cell's control centre, storing all your genetic information on chromosomes that you inherited from your parents.
Mitochondria are the powerhouses that release energy through aerobic respiration - basically, they keep your cells energised! Plant cells have extra bits: a cell wall made of cellulose for protection, chloroplasts containing chlorophyll to trap light for photosynthesis, and a large vacuole for support.
Quick Tip: Remember that plant cells have everything animal cells have, plus three extras: cell wall, chloroplasts, and a large vacuole!
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From Cells to You - The Big Picture
Cells are just the beginning of an amazing organisational system that builds up to create you! When similar cells group together to do the same job, they form tissues - like cardiac muscle tissue in your heart.
Different tissues then team up to create organs with specific functions. Your heart, for example, combines muscle tissue, nerve tissue, and blood vessels to pump blood around your body.
Organ systems form when multiple organs work together - your circulatory system includes your heart, blood vessels, and blood all cooperating. Finally, all your organ systems work together to create a complete organism - that's you!
Remember: It's like Russian dolls - cells fit into tissues, tissues into organs, organs into systems, and systems make you!
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
How Stuff Gets Around - Diffusion
Diffusion is simply the movement of molecules from where there's loads of them to where there's fewer - like how perfume spreads across a room. This process is crucial for getting oxygen, water, and glucose into cells, and removing waste like CO₂.
Three main factors affect how fast diffusion happens. Temperature speeds things up because particles have more kinetic energy to move around. A larger surface area of the cell membrane means more particles can cross at once.
The concentration gradient is probably the most important factor - the bigger the difference between high and low concentration areas, the faster diffusion occurs. It's like water flowing down a steep hill versus a gentle slope.
Resolution in microscopy refers to seeing two separate points as distinct after magnification - basically, how clear and detailed your view is when studying cells.
Pro Tip: Think of diffusion like people leaving a crowded concert - they naturally spread out from the packed venue to less crowded areas!
Sign up to see the contentIt's free!
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By signing up you accept Terms of Service and Privacy Policy
Three Types of Cells You Need to Know
Animal cells contain the basic kit: cell membrane, mitochondria, cytoplasm, nucleus, and nuclear membrane. They're like the standard model that does all the essential life functions.
Plant cells have everything animal cells do, plus their special extras for plant life. The cell wall provides extra protection, chloroplasts enable photosynthesis, and the large vacuole helps maintain structure and support.
Bacterial cells are the rebels - they're much simpler with a non-cellulose cell wall, cytoplasm, and genetic material floating freely as loops of DNA rather than organised in a nucleus. They also have plasmids, which are small rings of extra DNA.
Stem cells are the ultimate multitaskers - they can divide and differentiate into specialised cells. Adult stem cells (found in bone marrow) are limited in what they can become, whilst embryonic stem cells can potentially become any type of cell.
Key Point: The main difference between these cell types is complexity - bacterial cells are simplest, animal cells are more complex, and plant cells are the most complex with extra features!
We thought you’d never ask...
What is the Knowunity AI companion?
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.
Where can I download the Knowunity app?
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The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user