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sheila
07/12/2025
Biology
Amino Acids
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The Basic Structure of Amino Acids
Every amino acid follows the same basic blueprint, making them surprisingly simple to understand. Picture a central carbon atom with three key parts attached: an amine group (containing nitrogen), a carboxyl group (the acidic bit), and most importantly, an R group that makes each amino acid unique.
Think of amino acids like LEGO blocks - they all have the same connecting pieces (amine and carboxyl groups) but different coloured tops (the R groups). There are exactly 20 different amino acids in nature, each with its own special R group that gives it unique properties.
💡 Quick Tip: The R group is what matters most - it determines whether an amino acid is hydrophobic, hydrophilic, acidic, or basic, which ultimately affects how proteins fold and function.
These biological molecules contain carbon, hydrogen, nitrogen, and oxygen as standard, with some also containing sulfur for extra chemical versatility.
Building Peptide Bonds
When amino acids meet, they don't just sit next to each other - they actually join up through a clever chemical reaction. The amine group of one amino acid bonds with the carboxyl group of another, forming a peptide bond and releasing a water molecule in the process.
This condensation reaction happens in your ribosomes every time your cells make proteins. Two amino acids joined together create a dipeptide, whilst three or more form a polypeptide chain.
💡 Remember: This reaction needs a specific enzyme to make it happen quickly enough for life - your body doesn't leave protein synthesis to chance!
The beauty of this system is its simplicity - the same basic reaction repeated thousands of times can build incredibly complex molecules from just 20 different amino acid building blocks.
Breaking Down Proteins
Just as amino acids can join together, peptide bonds can be broken apart when needed. This reverse process is called hydrolysis - literally meaning "splitting with water" - and it's exactly what happens when you digest proteins in your food.
Protease enzymes in your digestive system carry out this hydrolysis reaction, adding water molecules back to break peptide bonds and release individual amino acids. Your body can then recycle these amino acids to build new proteins.
Here's the crucial bit: a polypeptide isn't quite the same as a protein yet. The polypeptide chain needs to fold into a complex 3D shape before it becomes a functional protein that can actually do its job in your body.
💡 Key Point: The sequence of amino acids determines how the protein folds, and the folding determines the function - get the sequence wrong, and the protein won't work properly.
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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.
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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.
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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 😍😁😲🤑💗✨🎀😮
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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
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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
Introduction to Amino Acids: Key Biological Molecules
Amino acids are the building blocks of proteins - essential biological molecules that make up everything from your muscles to enzymes. Understanding how these simple structures link together to form complex proteins is crucial for grasping how life works at... Show more
The Basic Structure of Amino Acids
Every amino acid follows the same basic blueprint, making them surprisingly simple to understand. Picture a central carbon atom with three key parts attached: an amine group (containing nitrogen), a carboxyl group (the acidic bit), and most importantly, an R group that makes each amino acid unique.
Think of amino acids like LEGO blocks - they all have the same connecting pieces (amine and carboxyl groups) but different coloured tops (the R groups). There are exactly 20 different amino acids in nature, each with its own special R group that gives it unique properties.
💡 Quick Tip: The R group is what matters most - it determines whether an amino acid is hydrophobic, hydrophilic, acidic, or basic, which ultimately affects how proteins fold and function.
These biological molecules contain carbon, hydrogen, nitrogen, and oxygen as standard, with some also containing sulfur for extra chemical versatility.
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Building Peptide Bonds
When amino acids meet, they don't just sit next to each other - they actually join up through a clever chemical reaction. The amine group of one amino acid bonds with the carboxyl group of another, forming a peptide bond and releasing a water molecule in the process.
This condensation reaction happens in your ribosomes every time your cells make proteins. Two amino acids joined together create a dipeptide, whilst three or more form a polypeptide chain.
💡 Remember: This reaction needs a specific enzyme to make it happen quickly enough for life - your body doesn't leave protein synthesis to chance!
The beauty of this system is its simplicity - the same basic reaction repeated thousands of times can build incredibly complex molecules from just 20 different amino acid building blocks.
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Breaking Down Proteins
Just as amino acids can join together, peptide bonds can be broken apart when needed. This reverse process is called hydrolysis - literally meaning "splitting with water" - and it's exactly what happens when you digest proteins in your food.
Protease enzymes in your digestive system carry out this hydrolysis reaction, adding water molecules back to break peptide bonds and release individual amino acids. Your body can then recycle these amino acids to build new proteins.
Here's the crucial bit: a polypeptide isn't quite the same as a protein yet. The polypeptide chain needs to fold into a complex 3D shape before it becomes a functional protein that can actually do its job in your body.
💡 Key Point: The sequence of amino acids determines how the protein folds, and the folding determines the function - get the sequence wrong, and the protein won't work properly.
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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