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Cool Science: How Proteins Work and Why DNA and RNA Aren't the Same

2

0

E

Eliza Kroeker

11/29/2025

AP Biology

Ch. 5 Notes - Organic Molecules

55

Nov 29, 2025

6 pages

Cool Science: How Proteins Work and Why DNA and RNA Aren't the Same

E

Eliza Kroeker

@elizakroeker_xrer

A comprehensive guide to fundamental biological molecules and their structures,... Show more

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PROTIENS
A) Proteins are formed from chains of amino
Dacids joined by peptide bonds.
All amino acids are composed of 1
groups/
Carbon bonded

Protein Structure Levels Continued

This section focuses on the higher levels of protein structure and their importance to protein function.

Definition: Tertiary structure refers to the three-dimensional configuration of an amino acid chain, while quaternary structure involves multiple polypeptides linked together.

Example: Hemoglobin exemplifies quaternary structure, being composed of four separate peptide chains.

Highlight: A protein's function is directly linked to its three-dimensional structure, and denaturation can prevent proper function.

PROTIENS
A) Proteins are formed from chains of amino
Dacids joined by peptide bonds.
All amino acids are composed of 1
groups/
Carbon bonded

Nucleic Acids: DNA and RNA

This section explores the fundamental components and roles of nucleic acids in biological systems.

Definition: Nucleic acids are polymers of nucleotides, each containing a five-carbon sugar, phosphate group, and nitrogenous base.

Vocabulary: DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) differ in their sugar components and base compositions.

Highlight: Nucleotides serve multiple functions beyond genetic material, including acting as cellular messengers and energy carriers.

PROTIENS
A) Proteins are formed from chains of amino
Dacids joined by peptide bonds.
All amino acids are composed of 1
groups/
Carbon bonded

Lipids and Fats

This section details the structure and functions of various lipid molecules in biological systems.

Definition: Lipids are organic molecules containing carbon, hydrogen, and oxygen, serving various biological functions including energy storage.

Example: Triglycerides consist of three fatty acids bound to a glycerol molecule, functioning in long-term energy storage.

Highlight: Phospholipids have unique amphipathic properties, making them crucial for cell membrane structure.

PROTIENS
A) Proteins are formed from chains of amino
Dacids joined by peptide bonds.
All amino acids are composed of 1
groups/
Carbon bonded

Carbohydrates

This section examines the various types of carbohydrates and their biological roles.

Definition: Carbohydrates range from simple monosaccharides to complex polysaccharides, serving both structural and energy storage functions.

Example: Glucose is a fundamental monosaccharide that serves as the building block for most polysaccharides.

Highlight: Different polysaccharides serve distinct functions: starch for plant energy storage, glycogen for animal energy storage, and cellulose for structural support.

PROTIENS
A) Proteins are formed from chains of amino
Dacids joined by peptide bonds.
All amino acids are composed of 1
groups/
Carbon bonded

Biological Molecules: Basic Principles

This section outlines the fundamental concepts regarding biological molecule classification and formation.

Definition: Organic molecules contain carbon and hydrogen, while inorganic molecules do not contain carbon.

Vocabulary: Dehydration synthesis joins monomers together by removing water, while hydrolysis splits molecules by adding water.

Highlight: Functional groups attached to carbon backbones determine the characteristics of different biological molecules.

PROTIENS
A) Proteins are formed from chains of amino
Dacids joined by peptide bonds.
All amino acids are composed of 1
groups/
Carbon bonded

Proteins: Structure and Formation

This section details the fundamental composition and structural organization of proteins. The text explains how amino acids combine to form complex protein structures through specific chemical bonds.

Definition: Proteins are polymers formed from amino acid chains joined by peptide bonds, with each amino acid containing specific functional groups attached to a central carbon atom.

Vocabulary: Peptide bonds are chemical bonds formed between the amino group of one amino acid and the carboxyl group of another.

Example: A polypeptide chain consists of 50 or more amino acids linked together.

Highlight: Protein structure can be organized into four distinct levels: primary, secondary, tertiary, and quaternary, each contributing to the protein's final form and function.



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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

I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

iOS user

Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

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

I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

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

I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

iOS user

Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

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

I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

Paul T

iOS user

 

AP Biology

55

Nov 29, 2025

6 pages

Cool Science: How Proteins Work and Why DNA and RNA Aren't the Same

E

Eliza Kroeker

@elizakroeker_xrer

A comprehensive guide to fundamental biological molecules and their structures, focusing on proteins, nucleic acids, lipids, and carbohydrates. The document explores their composition, formation, and biological significance.

Protein structure and function in biochemistryis explained through four structural levels,... Show more

PROTIENS
A) Proteins are formed from chains of amino
Dacids joined by peptide bonds.
All amino acids are composed of 1
groups/
Carbon bonded

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

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By signing up you accept Terms of Service and Privacy Policy

Protein Structure Levels Continued

This section focuses on the higher levels of protein structure and their importance to protein function.

Definition: Tertiary structure refers to the three-dimensional configuration of an amino acid chain, while quaternary structure involves multiple polypeptides linked together.

Example: Hemoglobin exemplifies quaternary structure, being composed of four separate peptide chains.

Highlight: A protein's function is directly linked to its three-dimensional structure, and denaturation can prevent proper function.

PROTIENS
A) Proteins are formed from chains of amino
Dacids joined by peptide bonds.
All amino acids are composed of 1
groups/
Carbon bonded

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

Nucleic Acids: DNA and RNA

This section explores the fundamental components and roles of nucleic acids in biological systems.

Definition: Nucleic acids are polymers of nucleotides, each containing a five-carbon sugar, phosphate group, and nitrogenous base.

Vocabulary: DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) differ in their sugar components and base compositions.

Highlight: Nucleotides serve multiple functions beyond genetic material, including acting as cellular messengers and energy carriers.

PROTIENS
A) Proteins are formed from chains of amino
Dacids joined by peptide bonds.
All amino acids are composed of 1
groups/
Carbon bonded

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

Lipids and Fats

This section details the structure and functions of various lipid molecules in biological systems.

Definition: Lipids are organic molecules containing carbon, hydrogen, and oxygen, serving various biological functions including energy storage.

Example: Triglycerides consist of three fatty acids bound to a glycerol molecule, functioning in long-term energy storage.

Highlight: Phospholipids have unique amphipathic properties, making them crucial for cell membrane structure.

PROTIENS
A) Proteins are formed from chains of amino
Dacids joined by peptide bonds.
All amino acids are composed of 1
groups/
Carbon bonded

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

Carbohydrates

This section examines the various types of carbohydrates and their biological roles.

Definition: Carbohydrates range from simple monosaccharides to complex polysaccharides, serving both structural and energy storage functions.

Example: Glucose is a fundamental monosaccharide that serves as the building block for most polysaccharides.

Highlight: Different polysaccharides serve distinct functions: starch for plant energy storage, glycogen for animal energy storage, and cellulose for structural support.

PROTIENS
A) Proteins are formed from chains of amino
Dacids joined by peptide bonds.
All amino acids are composed of 1
groups/
Carbon bonded

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

Biological Molecules: Basic Principles

This section outlines the fundamental concepts regarding biological molecule classification and formation.

Definition: Organic molecules contain carbon and hydrogen, while inorganic molecules do not contain carbon.

Vocabulary: Dehydration synthesis joins monomers together by removing water, while hydrolysis splits molecules by adding water.

Highlight: Functional groups attached to carbon backbones determine the characteristics of different biological molecules.

PROTIENS
A) Proteins are formed from chains of amino
Dacids joined by peptide bonds.
All amino acids are composed of 1
groups/
Carbon bonded

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

Proteins: Structure and Formation

This section details the fundamental composition and structural organization of proteins. The text explains how amino acids combine to form complex protein structures through specific chemical bonds.

Definition: Proteins are polymers formed from amino acid chains joined by peptide bonds, with each amino acid containing specific functional groups attached to a central carbon atom.

Vocabulary: Peptide bonds are chemical bonds formed between the amino group of one amino acid and the carboxyl group of another.

Example: A polypeptide chain consists of 50 or more amino acids linked together.

Highlight: Protein structure can be organized into four distinct levels: primary, secondary, tertiary, and quaternary, each contributing to the protein's final form and function.

We thought you’d never ask...

What is the Knowunity AI companion?

Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.

Where can I download the Knowunity app?

You can download the app in the Google Play Store and in the Apple App Store.

Is Knowunity really free of charge?

That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.

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4.9/5

App Store

4.8/5

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

I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

iOS user

Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

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

I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

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

I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

iOS user

Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

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

I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

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 app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

Paul T

iOS user