A comprehensive guide to protein and lipid structures, focusing on... Show more
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Subjects
Careers
Energy transfers (a2 only)
Infection and response
Homeostasis and response
Responding to change (a2 only)
Cell biology
Organisms respond to changes in their internal and external environments (a-level only)
Biological molecules
Organisation
Substance exchange
Bioenergetics
Genetic information & variation
Inheritance, variation and evolution
Genetics & ecosystems (a2 only)
Ecology
Cells
Show all topics
Medieval period: 1066 -1509
2m wars and welfare: britain in transition, 1906-1957
World war two & the holocaust
1l the quest for political stability: germany, 1871-1991
1f industrialisation and the people: britain, c1783-1885
Britain & the wider world: 1745 -1901
2d religious conflict and the church in england, c1529-c1570
The cold war
1c the tudors: england, 1485-1603
Inter-war germany
2j america: a nation divided, c1845-1877
2n revolution and dictatorship: russia, 1917-1953
2s the making of modern britain, 1951-2007
World war one
Britain: 1509 -1745
Show all topics
7
0
carys
12/07/2025
Biology
Unit 1 as level : protein and lipids
105
•
12 Jul 2025
•
carys
@carys_xewj
A comprehensive guide to protein and lipid structures, focusing on... Show more
This page explores the characteristics and importance of lipids in biological systems. Lipids are crucial organic molecules that serve multiple functions in living organisms.
Highlight: Lipids contain more energy per gram than carbohydrates and proteins, making them efficient energy storage molecules.
Definition: Fats are lipids that are solid at room temperature, while oils are liquid at room temperature.
Example: Glycerol combines with fatty acids to form more complex lipids.
This page details the structure and formation of triglycerides and phospholipids, emphasizing their molecular composition and behavior in aqueous environments.
Definition: Phospholipids are modified triglycerides where one fatty acid chain is replaced with a phosphate group.
Highlight: Phospholipids have both hydrophilic heads and hydrophobic tails, crucial for cell membrane formation.
Example: When mixed with water, phospholipids can form structures called micelles, with heads facing water and tails clustering together.
This page explores the various biological functions of lipids and their organizational structures in cellular systems.
Definition: A phospholipid bilayer is a double layer of phospholipids that forms the foundation of cell membranes.
Highlight: Lipids serve multiple crucial functions including protection of organs, thermal insulation, energy storage, and hormone production.
Example: Liposomes are spherical structures formed by phospholipid bilayers that trap water in their center.
This page details the four levels of protein structure and their importance in determining protein function.
Definition: Primary structure refers to the sequence of amino acids in a polypeptide chain.
Vocabulary: Alpha helix - A spiral structure held together by hydrogen bonds. Beta strand - An almost straight chain structure that can form pleated sheets.
Highlight: The tertiary structure creates unique active sites in enzymes through various types of bonds between R groups.
This page explores quaternary protein structure and distinguishes between globular and fibrous proteins.
Example: Hemoglobin, with its four polypeptide chains, exemplifies quaternary structure.
Definition: Globular proteins are water-soluble and include antibodies and hemoglobin, while fibrous proteins form tough, insoluble structures found in connective tissue.
Highlight: The final 3D structure of proteins can be either globular or fibrous, each with distinct properties and functions.
This page explains how proteins can lose their structure through various denaturing conditions.
Definition: Denaturation is the process where a protein's structure changes when the bonds maintaining its shape are broken.
Example: Hair perming involves breaking disulfide bonds to reshape protein structure.
Highlight: Different factors can cause denaturation, including high temperatures, extreme pH, and reducing agents.
This page introduces the fundamental building blocks of proteins and their formation process. Proteins are polymers composed of amino acids joined through condensation reactions to form polypeptide chains.
Definition: A polypeptide is a single chain of amino acids formed through condensation reactions, with one end containing a free amino group and the other a free carboxyl group.
Example: Glycine and alanine are examples of amino acids that can join to form dipeptides and eventually polypeptides.
Vocabulary: Condensation reaction - A chemical reaction where two molecules combine to form a larger molecule, releasing water as a byproduct.
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and 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
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
carys
@carys_xewj
A comprehensive guide to protein and lipid structures, focusing on their molecular composition, formation, and biological functions. The text explores how protein polymer structure and functionare determined by amino acid sequences and various structural levels, while lipids serve crucial... Show more
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page explores the characteristics and importance of lipids in biological systems. Lipids are crucial organic molecules that serve multiple functions in living organisms.
Highlight: Lipids contain more energy per gram than carbohydrates and proteins, making them efficient energy storage molecules.
Definition: Fats are lipids that are solid at room temperature, while oils are liquid at room temperature.
Example: Glycerol combines with fatty acids to form more complex lipids.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page details the structure and formation of triglycerides and phospholipids, emphasizing their molecular composition and behavior in aqueous environments.
Definition: Phospholipids are modified triglycerides where one fatty acid chain is replaced with a phosphate group.
Highlight: Phospholipids have both hydrophilic heads and hydrophobic tails, crucial for cell membrane formation.
Example: When mixed with water, phospholipids can form structures called micelles, with heads facing water and tails clustering together.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page explores the various biological functions of lipids and their organizational structures in cellular systems.
Definition: A phospholipid bilayer is a double layer of phospholipids that forms the foundation of cell membranes.
Highlight: Lipids serve multiple crucial functions including protection of organs, thermal insulation, energy storage, and hormone production.
Example: Liposomes are spherical structures formed by phospholipid bilayers that trap water in their center.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page details the four levels of protein structure and their importance in determining protein function.
Definition: Primary structure refers to the sequence of amino acids in a polypeptide chain.
Vocabulary: Alpha helix - A spiral structure held together by hydrogen bonds. Beta strand - An almost straight chain structure that can form pleated sheets.
Highlight: The tertiary structure creates unique active sites in enzymes through various types of bonds between R groups.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page explores quaternary protein structure and distinguishes between globular and fibrous proteins.
Example: Hemoglobin, with its four polypeptide chains, exemplifies quaternary structure.
Definition: Globular proteins are water-soluble and include antibodies and hemoglobin, while fibrous proteins form tough, insoluble structures found in connective tissue.
Highlight: The final 3D structure of proteins can be either globular or fibrous, each with distinct properties and functions.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page explains how proteins can lose their structure through various denaturing conditions.
Definition: Denaturation is the process where a protein's structure changes when the bonds maintaining its shape are broken.
Example: Hair perming involves breaking disulfide bonds to reshape protein structure.
Highlight: Different factors can cause denaturation, including high temperatures, extreme pH, and reducing agents.
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
This page introduces the fundamental building blocks of proteins and their formation process. Proteins are polymers composed of amino acids joined through condensation reactions to form polypeptide chains.
Definition: A polypeptide is a single chain of amino acids formed through condensation reactions, with one end containing a free amino group and the other a free carboxyl group.
Example: Glycine and alanine are examples of amino acids that can join to form dipeptides and eventually polypeptides.
Vocabulary: Condensation reaction - A chemical reaction where two molecules combine to form a larger molecule, releasing water as a byproduct.
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and 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
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