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Updated Mar 20, 2026
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Every living thing around you - from your pet dog... Show more







Cells are literally everywhere in the living world, and they're working non-stop to keep organisms alive. You can't see them without a microscope because they're incredibly small, but they're doing all the heavy lifting behind the scenes.
Each cell is packed with smaller parts called organelles - think of them as tiny workers, each with their own specific job. Just like how your school has different departments (office, canteen, library), cells have different organelles handling different tasks.
The brilliant thing about cells is that once you understand the basics, you'll start seeing patterns everywhere in biology. It's like learning the rules of a game - suddenly everything else makes sense!
Quick Tip: Remember that a cell is the smallest unit that can still be called "alive" - it's where all life processes actually happen.

Your body is made up of billions of animal cells, each one working like a tiny factory. Every animal cell has four main parts that you absolutely need to know for your exams.
The nucleus is the boss of the cell - it contains all the DNA instructions and tells everything else what to do. The cytoplasm is like a jelly-filled workspace where most chemical reactions happen, and all the other parts float around in it.
The cell membrane acts like a security guard, deciding what can enter and leave the cell. Meanwhile, the mitochondria are the power stations, breaking down glucose during respiration to release energy for the cell.
Exam Alert: Cells that need lots of energy (like muscle cells) are packed with mitochondria - this connection often comes up in test questions!

Here's where it gets interesting - plant cells have everything that animal cells have, plus three extra bits that make them special. These extras are what allow plants to stand tall and make their own food.
The cell wall is a tough outer layer made of cellulose that gives the plant structure and support. Without it, plants would be floppy like jelly! Chloroplasts are the green organelles containing chlorophyll that capture sunlight for photosynthesis.
The permanent vacuole is a massive water-filled space that pushes against the cell wall to keep the plant cell firm and rigid. Animal cells might have tiny vacuoles, but plant cells have one huge permanent one.
Common Mistake: Don't think plant cells don't need mitochondria just because they photosynthesise - they still need to respire to release energy from the food they make!

The easiest way to remember the differences is that plant cells are basically animal cells with three bonus features. Both types have nucleus, cytoplasm, cell membrane, and mitochondria - these are the universal basics.
Animal cells are typically irregular and wobbly in shape because they only have a flexible cell membrane holding them together. Plant cells are usually rectangular and rigid because of their tough cell wall structure.
The key differences are: cell wall (plants only), chloroplasts (plants only), and large permanent vacuole (plants only). If you spot any of these three under a microscope, you're definitely looking at a plant cell.
Memory Trick: Think "Plants are Posh" - they have three Permanent extras (wall, chloroplasts, vacuole) that animals don't bother with!

Understanding what each organelle actually does is crucial for exam success - you can't just memorise names and locations. The nucleus controls everything with DNA, cytoplasm hosts chemical reactions, and the cell membrane controls entry and exit.
Mitochondria release energy through respiration, while chloroplasts (plants only) capture light energy for photosynthesis. The cell wall provides structural support, and the permanent vacuole maintains cell pressure and firmness.
Top exam mistakes to avoid: Don't confuse cell wall with cell membrane, remember that plant cells need both mitochondria AND chloroplasts, and always explain the function when labelling diagrams.
Exam Success: Practice drawing and labelling both cell types from memory - this active recall method will stick much better than just reading notes!

Animal cells have the four essentials: nucleus (control centre), cytoplasm (reaction space), cell membrane (security), and mitochondria (power stations). These are found in every animal cell from humans to hamsters.
Plant cells have those same four basics PLUS their three special additions: cell wall (support structure), chloroplasts (food factories), and permanent vacuole (pressure system). This is why plants can stand upright and feed themselves.
The beauty of cell biology is that these same principles apply whether you're studying a massive redwood tree or a tiny bacterium. Master these basics now, and you'll find the rest of biology much easier to understand.
Final Tip: Make flashcards with organelle names on one side and functions on the other - test yourself regularly and you'll ace any cell question!
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
You can download the app in the Google Play Store and in the 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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE Knowunity AI. 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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE Knowunity AI. 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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user
Every living thing around you - from your pet dog to the massive oak tree in your garden - is built from tiny building blocks called cells. Think of cells like LEGO bricks that stack together to create everything alive,... Show more

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Improve your grades
Join milions of students
Cells are literally everywhere in the living world, and they're working non-stop to keep organisms alive. You can't see them without a microscope because they're incredibly small, but they're doing all the heavy lifting behind the scenes.
Each cell is packed with smaller parts called organelles - think of them as tiny workers, each with their own specific job. Just like how your school has different departments (office, canteen, library), cells have different organelles handling different tasks.
The brilliant thing about cells is that once you understand the basics, you'll start seeing patterns everywhere in biology. It's like learning the rules of a game - suddenly everything else makes sense!
Quick Tip: Remember that a cell is the smallest unit that can still be called "alive" - it's where all life processes actually happen.

Access to all documents
Improve your grades
Join milions of students
Your body is made up of billions of animal cells, each one working like a tiny factory. Every animal cell has four main parts that you absolutely need to know for your exams.
The nucleus is the boss of the cell - it contains all the DNA instructions and tells everything else what to do. The cytoplasm is like a jelly-filled workspace where most chemical reactions happen, and all the other parts float around in it.
The cell membrane acts like a security guard, deciding what can enter and leave the cell. Meanwhile, the mitochondria are the power stations, breaking down glucose during respiration to release energy for the cell.
Exam Alert: Cells that need lots of energy (like muscle cells) are packed with mitochondria - this connection often comes up in test questions!

Access to all documents
Improve your grades
Join milions of students
Here's where it gets interesting - plant cells have everything that animal cells have, plus three extra bits that make them special. These extras are what allow plants to stand tall and make their own food.
The cell wall is a tough outer layer made of cellulose that gives the plant structure and support. Without it, plants would be floppy like jelly! Chloroplasts are the green organelles containing chlorophyll that capture sunlight for photosynthesis.
The permanent vacuole is a massive water-filled space that pushes against the cell wall to keep the plant cell firm and rigid. Animal cells might have tiny vacuoles, but plant cells have one huge permanent one.
Common Mistake: Don't think plant cells don't need mitochondria just because they photosynthesise - they still need to respire to release energy from the food they make!

Access to all documents
Improve your grades
Join milions of students
The easiest way to remember the differences is that plant cells are basically animal cells with three bonus features. Both types have nucleus, cytoplasm, cell membrane, and mitochondria - these are the universal basics.
Animal cells are typically irregular and wobbly in shape because they only have a flexible cell membrane holding them together. Plant cells are usually rectangular and rigid because of their tough cell wall structure.
The key differences are: cell wall (plants only), chloroplasts (plants only), and large permanent vacuole (plants only). If you spot any of these three under a microscope, you're definitely looking at a plant cell.
Memory Trick: Think "Plants are Posh" - they have three Permanent extras (wall, chloroplasts, vacuole) that animals don't bother with!

Access to all documents
Improve your grades
Join milions of students
Understanding what each organelle actually does is crucial for exam success - you can't just memorise names and locations. The nucleus controls everything with DNA, cytoplasm hosts chemical reactions, and the cell membrane controls entry and exit.
Mitochondria release energy through respiration, while chloroplasts (plants only) capture light energy for photosynthesis. The cell wall provides structural support, and the permanent vacuole maintains cell pressure and firmness.
Top exam mistakes to avoid: Don't confuse cell wall with cell membrane, remember that plant cells need both mitochondria AND chloroplasts, and always explain the function when labelling diagrams.
Exam Success: Practice drawing and labelling both cell types from memory - this active recall method will stick much better than just reading notes!

Access to all documents
Improve your grades
Join milions of students
Animal cells have the four essentials: nucleus (control centre), cytoplasm (reaction space), cell membrane (security), and mitochondria (power stations). These are found in every animal cell from humans to hamsters.
Plant cells have those same four basics PLUS their three special additions: cell wall (support structure), chloroplasts (food factories), and permanent vacuole (pressure system). This is why plants can stand upright and feed themselves.
The beauty of cell biology is that these same principles apply whether you're studying a massive redwood tree or a tiny bacterium. Master these basics now, and you'll find the rest of biology much easier to understand.
Final Tip: Make flashcards with organelle names on one side and functions on the other - test yourself regularly and you'll ace any cell question!
Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.
You can download the app in the Google Play Store and in the Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
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Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Practice Test ✓ Essay Outlines
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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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE Knowunity AI. 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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
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
I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️
Thomas R
iOS user
Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀
Marco B
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE Knowunity AI. 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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!
Paul T
iOS user