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Cell Organelles: The Building Blocks of Life
Think of organelles as the specialized departments in a cell's factory. Each one has a specific job that keeps the cell alive and functioning properly.
The cell-surface membrane acts like a selective security gate around the cell. It's made of a phospholipid bilayer with proteins, cholesterol, and special recognition molecules called glycoproteins and glycolipids. This structure is known as the fluid-mosaic model because it's flexible and contains various types of molecules that can move around.
The nucleus is basically the cell's control center, surrounded by a nuclear envelope with tiny doorways called nuclear pores. Inside, you'll find chromosomes (your DNA) and the nucleolus, which churns out ribosomes like a factory producing protein-making machines.
Mitochondria are the cell's powerhouses, featuring a double membrane with folded inner sections called cristae. They're where aerobic respiration happens, converting glucose into ATP - the cell's energy currency. Meanwhile, chloroplasts (found only in plants) have a similar double membrane structure but contain thylakoids packed with chlorophyll for photosynthesis.
💡 Quick Tip: Remember that mitochondria and chloroplasts both have double membranes because they likely evolved from ancient bacteria!
The Golgi apparatus works like a post office, modifying and packaging proteins in stacked membranes called cisternae. Lysosomes are special Golgi vesicles filled with digestive enzymes that break down waste. Ribosomes are the actual protein factories, whilst the endoplasmic reticulum provides highways for transport - the RER (with ribosomes attached) handles proteins, and the SER deals with lipids.
Plant cells get extra support from their cell wall made of cellulose, plus a large cell vacuole surrounded by a tonoplast membrane for storage and structural support. The cytoskeleton runs throughout all cells like scaffolding, providing strength and helping organelles move around.
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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.
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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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Elisha
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Comprehensive Guide to Organelles in Eukaryotic Cells
Every cell in your body is like a bustling city, packed with tiny structures called organelles that keep everything running smoothly. Understanding what each organelle does is crucial for grasping how life works at the most basic level - and... Show more
Cell Organelles: The Building Blocks of Life
Think of organelles as the specialized departments in a cell's factory. Each one has a specific job that keeps the cell alive and functioning properly.
The cell-surface membrane acts like a selective security gate around the cell. It's made of a phospholipid bilayer with proteins, cholesterol, and special recognition molecules called glycoproteins and glycolipids. This structure is known as the fluid-mosaic model because it's flexible and contains various types of molecules that can move around.
The nucleus is basically the cell's control center, surrounded by a nuclear envelope with tiny doorways called nuclear pores. Inside, you'll find chromosomes (your DNA) and the nucleolus, which churns out ribosomes like a factory producing protein-making machines.
Mitochondria are the cell's powerhouses, featuring a double membrane with folded inner sections called cristae. They're where aerobic respiration happens, converting glucose into ATP - the cell's energy currency. Meanwhile, chloroplasts (found only in plants) have a similar double membrane structure but contain thylakoids packed with chlorophyll for photosynthesis.
💡 Quick Tip: Remember that mitochondria and chloroplasts both have double membranes because they likely evolved from ancient bacteria!
The Golgi apparatus works like a post office, modifying and packaging proteins in stacked membranes called cisternae. Lysosomes are special Golgi vesicles filled with digestive enzymes that break down waste. Ribosomes are the actual protein factories, whilst the endoplasmic reticulum provides highways for transport - the RER (with ribosomes attached) handles proteins, and the SER deals with lipids.
Plant cells get extra support from their cell wall made of cellulose, plus a large cell vacuole surrounded by a tonoplast membrane for storage and structural support. The cytoskeleton runs throughout all cells like scaffolding, providing strength and helping organelles move around.
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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
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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
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David K
iOS user
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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
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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 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
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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.
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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.
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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.
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Xander S
iOS user
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Elisha
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Paul T
iOS user