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Understanding Enzyme Inhibition: A-Level Biology Notes
Milkshakemi
@milkshakemi
![Tonc: Brategical Watarukes
[1.9 Enzyme inhibition]
SPEC POINT: 3.1 Biological Molecules
3.1.4 Proteins
3.1.4.2 Many proteins are enzymes
S](/_next/image?url=https%3A%2F%2Fcontent-eu-central-1.knowunity.com%2FCONTENT%2FCvGeCTLoeHwcfQlVZwRP_image_page_1.webp&w=2048&q=75)
Enzyme Inhibitors: Types and Functions
Enzyme inhibitors are substances that interfere with an enzyme's active site, reducing its activity and slowing down biochemical reactions. These molecules play crucial roles in regulating cellular processes and are the basis for many medications.
There are two main types of enzyme inhibitors you need to know. Competitive inhibitors have a molecular structure similar to the enzyme's substrate, allowing them to occupy the active site. As the name suggests, they literally compete with the substrate for binding to the enzyme, which temporarily prevents the normal reaction from occurring.
The effectiveness of competitive inhibition depends on the relative concentrations of both inhibitor and substrate. When substrate concentration increases, it can overcome the inhibitory effect since more substrate molecules are available to outcompete the inhibitor for binding spots.
Remember this! Competitive inhibition can be overcome by increasing substrate concentration - this is a key characteristic that distinguishes it from non-competitive inhibition and often appears in exam questions.
Real-world examples include malonate inhibiting respiratory enzymes that normally act on succinate, and penicillin inhibiting the bacterial enzyme transpeptidase - which is how this antibiotic kills bacteria!
![Tonc: Brategical Watarukes
[1.9 Enzyme inhibition]
SPEC POINT: 3.1 Biological Molecules
3.1.4 Proteins
3.1.4.2 Many proteins are enzymes
S](/_next/image?url=https%3A%2F%2Fcontent-eu-central-1.knowunity.com%2FCONTENT%2FCvGeCTLoeHwcfQlVZwRP_image_page_2.webp&w=2048&q=75)
Non-Competitive Inhibition
Non-competitive inhibitors work quite differently from their competitive counterparts. Rather than binding to the active site, these inhibitors attach to a different part of the enzyme molecule—called the binding site.
When a non-competitive inhibitor binds, it causes a structural change in the enzyme, distorting the active site's shape. This distortion means the substrate can no longer fit properly, preventing the reaction even though the substrate isn't directly blocked from approaching the active site.
The key distinction is that increasing substrate concentration doesn't reduce the effect of non-competitive inhibitors. Since the inhibitor and substrate aren't competing for the same binding location, adding more substrate molecules won't help—the enzyme's shape remains altered regardless of how many substrate molecules are present.
Quick tip: Think of non-competitive inhibitors as changing the enzyme's "lock" (active site) so that even the correct "key" (substrate) no longer fits properly. This makes them particularly effective even at low concentrations.
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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.
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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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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
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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.
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
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Understanding Enzyme Inhibition: A-Level Biology Notes
Milkshakemi
@milkshakemi
Enzyme inhibition is a crucial process that interferes with enzyme function in biological systems. Understanding how different inhibitors affect enzyme activity helps explain important biological processes, drug actions, and metabolic regulation that occur within living organisms.
Enzyme Inhibitors: Types and Functions
Enzyme inhibitors are substances that interfere with an enzyme's active site, reducing its activity and slowing down biochemical reactions. These molecules play crucial roles in regulating cellular processes and are the basis for many medications.
There are two main types of enzyme inhibitors you need to know. Competitive inhibitors have a molecular structure similar to the enzyme's substrate, allowing them to occupy the active site. As the name suggests, they literally compete with the substrate for binding to the enzyme, which temporarily prevents the normal reaction from occurring.
The effectiveness of competitive inhibition depends on the relative concentrations of both inhibitor and substrate. When substrate concentration increases, it can overcome the inhibitory effect since more substrate molecules are available to outcompete the inhibitor for binding spots.
Remember this! Competitive inhibition can be overcome by increasing substrate concentration - this is a key characteristic that distinguishes it from non-competitive inhibition and often appears in exam questions.
Real-world examples include malonate inhibiting respiratory enzymes that normally act on succinate, and penicillin inhibiting the bacterial enzyme transpeptidase - which is how this antibiotic kills bacteria!
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Non-Competitive Inhibition
Non-competitive inhibitors work quite differently from their competitive counterparts. Rather than binding to the active site, these inhibitors attach to a different part of the enzyme molecule—called the binding site.
When a non-competitive inhibitor binds, it causes a structural change in the enzyme, distorting the active site's shape. This distortion means the substrate can no longer fit properly, preventing the reaction even though the substrate isn't directly blocked from approaching the active site.
The key distinction is that increasing substrate concentration doesn't reduce the effect of non-competitive inhibitors. Since the inhibitor and substrate aren't competing for the same binding location, adding more substrate molecules won't help—the enzyme's shape remains altered regardless of how many substrate molecules are present.
Quick tip: Think of non-competitive inhibitors as changing the enzyme's "lock" (active site) so that even the correct "key" (substrate) no longer fits properly. This makes them particularly effective even at low concentrations.
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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
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
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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