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23 Dec 2025
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Understanding Cellular Respiration: ATP Production Simplified
Eve
@eve_cuthbertson
Overview of Cellular Respiration
Think of cellular respiration as your body's power plant - it's constantly converting glucose into ATP, the energy currency that keeps you alive. The process starts with glycolysis in your cell's cytoplasm and can continue in two different ways depending on whether oxygen is available.
When oxygen is present, glucose gets completely broken down through the citric acid cycle and electron transport chain in your mitochondria. This aerobic pathway produces loads of ATP - around 32 molecules per glucose! Without oxygen, your cells switch to fermentation, which only gives you the 2 ATP from glycolysis.
The whole system relies on moving electrons and hydrogen ions around using special helper molecules called coenzymes like NAD and FAD. These act like shuttle buses, carrying the good stuff to where it's needed most.
Key Point: Oxygen acts as the final electron acceptor - without it, the whole efficient system grinds to a halt!
The Three Stages Explained
Glycolysis happens first and requires an upfront investment of 2 ATP to get going (like paying to enter a casino). But don't worry - you get 4 ATP back in the energy pay-off phase, giving you a net gain of 2 ATP. The dehydrogenase enzymes also produce NADH₂ by grabbing hydrogen ions and electrons from glucose.
When oxygen's available, pyruvate (glycolysis's end product) gets converted into acetyl coenzyme A, which enters the citric acid cycle. Here, acetyl groups combine with oxaloacetate to form citrate, then go through a series of reactions that regenerate oxaloacetate whilst producing more ATP, CO₂, and loaded coenzymes (NADH₂ and FADH₂).
The real energy jackpot happens at the electron transport chain in your mitochondria's inner membrane. As electrons move down the chain, they release energy that pumps hydrogen ions across the membrane. When these ions flow back through ATP synthase, they generate ATP - like water flowing through a turbine to make electricity.
Remember: The electron transport chain is where most of your ATP comes from - it's the powerhouse within the powerhouse!
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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
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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
Understanding Cellular Respiration: ATP Production Simplified
Eve
@eve_cuthbertson
Cellular respiration is how your cells turn glucose into the energy currency ATP that powers everything you do. This process involves three main stages: glycolysis, the citric acid cycle, and the electron transport chain, each playing a crucial role in... Show more
Overview of Cellular Respiration
Think of cellular respiration as your body's power plant - it's constantly converting glucose into ATP, the energy currency that keeps you alive. The process starts with glycolysis in your cell's cytoplasm and can continue in two different ways depending on whether oxygen is available.
When oxygen is present, glucose gets completely broken down through the citric acid cycle and electron transport chain in your mitochondria. This aerobic pathway produces loads of ATP - around 32 molecules per glucose! Without oxygen, your cells switch to fermentation, which only gives you the 2 ATP from glycolysis.
The whole system relies on moving electrons and hydrogen ions around using special helper molecules called coenzymes like NAD and FAD. These act like shuttle buses, carrying the good stuff to where it's needed most.
Key Point: Oxygen acts as the final electron acceptor - without it, the whole efficient system grinds to a halt!
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The Three Stages Explained
Glycolysis happens first and requires an upfront investment of 2 ATP to get going (like paying to enter a casino). But don't worry - you get 4 ATP back in the energy pay-off phase, giving you a net gain of 2 ATP. The dehydrogenase enzymes also produce NADH₂ by grabbing hydrogen ions and electrons from glucose.
When oxygen's available, pyruvate (glycolysis's end product) gets converted into acetyl coenzyme A, which enters the citric acid cycle. Here, acetyl groups combine with oxaloacetate to form citrate, then go through a series of reactions that regenerate oxaloacetate whilst producing more ATP, CO₂, and loaded coenzymes (NADH₂ and FADH₂).
The real energy jackpot happens at the electron transport chain in your mitochondria's inner membrane. As electrons move down the chain, they release energy that pumps hydrogen ions across the membrane. When these ions flow back through ATP synthase, they generate ATP - like water flowing through a turbine to make electricity.
Remember: The electron transport chain is where most of your ATP comes from - it's the powerhouse within the powerhouse!
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What is the Knowunity AI companion?
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Where can I download the Knowunity app?
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Most popular content: Cellular Respiration
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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