Subjects
Biology
Chemistry
AP Chemistry
English
AP English Literature
Biology
Dec 9, 2025
70
23 pages
Ian Steigerwald @ian_runningxc
Proteins are incredibly versatile molecules that perform countless essential functions in living organisms. From forming structural components like... Show more
Proteins are among the most diverse and important molecules in living organisms. They perform countless crucial functions that keep your body running smoothly.
Think of proteins as the ultimate multitaskers in your body. They form your hair and muscles, store nutrients, transport substances in and out of cells, and even defend against harmful microorganisms.
Without proteins, your cells couldn't communicate with each other, control chemical reactions, or maintain their structure. Their versatility makes them essential building blocks for all living things.
Fun Fact There are likely more than 100,000 different types of proteins in the human body, each with a specific job!
Proteins are made up of smaller units called amino acids. These tiny molecules contain carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur.
Each amino acid has the same basic structure a central carbon atom connected to four different partners. These include an amino group, a hydrogen atom, a carboxyl group, and an "R group" that varies between different amino acids.
The R group is what makes each amino acid unique. There are 20 different amino acids because there are 20 different possible R groups. Your body can produce 12 of these amino acids on its own, but the other 8 must come from the food you eat - these are called essential amino acids.
Remember You need to eat foods containing the 8 essential amino acids your body can't make, which is why having a varied diet is important!
Amino acids join together through strong chemical connections called peptide bonds. When many amino acids link up (usually 100 or more), they form a long chain called a polypeptide.
Proteins can consist of one or more polypeptide chains twisted and folded together. Think of amino acids as letters, polypeptides as sentences, and the complete protein as a paragraph with specific instructions.
The sequence of amino acids in a protein is incredibly important - it's like a code that determines exactly what the protein will do in your body. Change just one amino acid, and the protein might not function properly!
Important The human body contains about 100,000 different types of proteins, each with its own unique sequence of amino acids!
After a polypeptide chain forms, it doesn't stay straight - it folds into a specific three-dimensional shape. This folding happens because amino acids in different parts of the chain interact through hydrogen bonding.
The folded shape of a protein is crucial to its function. Just like a key needs a specific shape to fit a lock, proteins must have the correct shape to do their job. If a protein doesn't fold properly, it usually can't function.
Even a small change in the amino acid sequence can alter how a protein folds. This is why genetic mutations that change just one amino acid can sometimes cause serious diseases - they create proteins with the wrong shape.
Think about it Proteins are like origami - it's not just about having the right paper (amino acids), but folding it in exactly the right way to create something functional!
Denaturation happens when a protein unravels from its normal shape due to environmental changes. Heat, extreme pH, or certain chemicals can cause proteins to denature.
A classic example of denaturation is frying an egg - the clear, liquid egg white turns solid and white because the heat denatures its proteins. When proteins lose their shape, they also lose their function.
This is why high fevers can be dangerous - if your body temperature gets too high, proteins throughout your body may begin to denature and stop working properly. Similarly, our bodies maintain a specific pH because proteins function best within a narrow pH range.
Real-world connection Next time you cook an egg, you're watching protein denaturation in action - the transformation from liquid to solid white is proteins unfolding due to heat!
Enzymes are special proteins that speed up chemical reactions in your body. They work as biological catalysts by lowering the activation energy - the energy required for a reaction to begin.
Without enzymes, most reactions in your body would happen too slowly to sustain life. For example, it would take years to digest your lunch without digestive enzymes!
Enzymes make reactions happen faster at your body's normal temperature, allowing thousands of essential chemical processes to occur every second in your cells. Each enzyme is highly specialized for a particular reaction.
Analogy If a chemical reaction is like pushing a boulder uphill, an enzyme creates a gentler slope, making the task much easier and faster!
Enzymes have a special area called the active site where specific molecules fit, much like a key fits into a lock. The molecule that an enzyme works on is called the substrate.
When a substrate enters an enzyme's active site, they form an enzyme-substrate complex. The enzyme holds the substrate in position, making it easier for the reaction to occur. After the reaction, the products are released, and the enzyme is free to work on another substrate.
This lock-and-key mechanism explains why enzymes are so specific - each enzyme typically works with just one type of substrate or reaction. Your body has thousands of different enzymes, each designed for a particular job.
Did you know? Some enzymes can process millions of substrate molecules per second - they're among the most efficient workers in nature!
Since enzymes are proteins, they can also be denatured by extreme conditions. When an enzyme denatures, its active site changes shape, and it can no longer bind to its substrate.
Temperature, pH, and certain chemicals can all affect enzyme function. Each enzyme works best at specific conditions - for example, digestive enzymes in your stomach function well in acidic environments, while enzymes in your blood need a neutral pH.
In lab experiments, you can observe enzyme activity by watching how quickly they break down substrates. For instance, the enzyme catalase (found in liver cells) breaks down hydrogen peroxide into water and oxygen gas, creating visible bubbles.
Application Understanding enzyme sensitivity helps explain why your body temperature and pH must be carefully regulated - even small changes can slow down or stop essential enzymatic reactions!
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.
You can download the app in the Google Play Store and in the Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
5
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the principles of ecotourism, focusing on its environmental, economic, and social benefits. This summary covers key concepts such as conservation, stewardship, and sustainable development, highlighting how ecotourism supports local communities while preserving natural habitats. Ideal for geography students seeking to understand the impact of tourism on the environment.
Biologyintroductory chapter
Biologyincluding the different types of tissues, their functions, and their locations.
BiologyNotes describing energy flow in ecosystems
BiologyApp 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
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
Ian Steigerwald
@ian_runningxc
Proteins are incredibly versatile molecules that perform countless essential functions in living organisms. From forming structural components like hair to controlling chemical reactions in cells, proteins are fundamental to life. Understanding their structure and function is key to grasping how... Show more
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Improve your grades
Join milions of students
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Proteins are among the most diverse and important molecules in living organisms. They perform countless crucial functions that keep your body running smoothly.
Think of proteins as the ultimate multitaskers in your body. They form your hair and muscles, store nutrients, transport substances in and out of cells, and even defend against harmful microorganisms.
Without proteins, your cells couldn't communicate with each other, control chemical reactions, or maintain their structure. Their versatility makes them essential building blocks for all living things.
Fun Fact: There are likely more than 100,000 different types of proteins in the human body, each with a specific job!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Proteins are made up of smaller units called amino acids. These tiny molecules contain carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur.
Each amino acid has the same basic structure: a central carbon atom connected to four different partners. These include an amino group, a hydrogen atom, a carboxyl group, and an "R group" that varies between different amino acids.
The R group is what makes each amino acid unique. There are 20 different amino acids because there are 20 different possible R groups. Your body can produce 12 of these amino acids on its own, but the other 8 must come from the food you eat - these are called essential amino acids.
Remember: You need to eat foods containing the 8 essential amino acids your body can't make, which is why having a varied diet is important!
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Amino acids join together through strong chemical connections called peptide bonds. When many amino acids link up (usually 100 or more), they form a long chain called a polypeptide.
Proteins can consist of one or more polypeptide chains twisted and folded together. Think of amino acids as letters, polypeptides as sentences, and the complete protein as a paragraph with specific instructions.
The sequence of amino acids in a protein is incredibly important - it's like a code that determines exactly what the protein will do in your body. Change just one amino acid, and the protein might not function properly!
Important: The human body contains about 100,000 different types of proteins, each with its own unique sequence of amino acids!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
After a polypeptide chain forms, it doesn't stay straight - it folds into a specific three-dimensional shape. This folding happens because amino acids in different parts of the chain interact through hydrogen bonding.
The folded shape of a protein is crucial to its function. Just like a key needs a specific shape to fit a lock, proteins must have the correct shape to do their job. If a protein doesn't fold properly, it usually can't function.
Even a small change in the amino acid sequence can alter how a protein folds. This is why genetic mutations that change just one amino acid can sometimes cause serious diseases - they create proteins with the wrong shape.
Think about it: Proteins are like origami - it's not just about having the right paper (amino acids), but folding it in exactly the right way to create something functional!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Denaturation happens when a protein unravels from its normal shape due to environmental changes. Heat, extreme pH, or certain chemicals can cause proteins to denature.
A classic example of denaturation is frying an egg - the clear, liquid egg white turns solid and white because the heat denatures its proteins. When proteins lose their shape, they also lose their function.
This is why high fevers can be dangerous - if your body temperature gets too high, proteins throughout your body may begin to denature and stop working properly. Similarly, our bodies maintain a specific pH because proteins function best within a narrow pH range.
Real-world connection: Next time you cook an egg, you're watching protein denaturation in action - the transformation from liquid to solid white is proteins unfolding due to heat!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Enzymes are special proteins that speed up chemical reactions in your body. They work as biological catalysts by lowering the activation energy - the energy required for a reaction to begin.
Without enzymes, most reactions in your body would happen too slowly to sustain life. For example, it would take years to digest your lunch without digestive enzymes!
Enzymes make reactions happen faster at your body's normal temperature, allowing thousands of essential chemical processes to occur every second in your cells. Each enzyme is highly specialized for a particular reaction.
Analogy: If a chemical reaction is like pushing a boulder uphill, an enzyme creates a gentler slope, making the task much easier and faster!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Enzymes have a special area called the active site where specific molecules fit, much like a key fits into a lock. The molecule that an enzyme works on is called the substrate.
When a substrate enters an enzyme's active site, they form an enzyme-substrate complex. The enzyme holds the substrate in position, making it easier for the reaction to occur. After the reaction, the products are released, and the enzyme is free to work on another substrate.
This lock-and-key mechanism explains why enzymes are so specific - each enzyme typically works with just one type of substrate or reaction. Your body has thousands of different enzymes, each designed for a particular job.
Did you know? Some enzymes can process millions of substrate molecules per second - they're among the most efficient workers in nature!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Since enzymes are proteins, they can also be denatured by extreme conditions. When an enzyme denatures, its active site changes shape, and it can no longer bind to its substrate.
Temperature, pH, and certain chemicals can all affect enzyme function. Each enzyme works best at specific conditions - for example, digestive enzymes in your stomach function well in acidic environments, while enzymes in your blood need a neutral pH.
In lab experiments, you can observe enzyme activity by watching how quickly they break down substrates. For instance, the enzyme catalase (found in liver cells) breaks down hydrogen peroxide into water and oxygen gas, creating visible bubbles.
Application: Understanding enzyme sensitivity helps explain why your body temperature and pH must be carefully regulated - even small changes can slow down or stop essential enzymatic reactions!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
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.
You can download the app in the Google Play Store and in the Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
5
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Explore the principles of ecotourism, focusing on its environmental, economic, and social benefits. This summary covers key concepts such as conservation, stewardship, and sustainable development, highlighting how ecotourism supports local communities while preserving natural habitats. Ideal for geography students seeking to understand the impact of tourism on the environment.
Biologyintroductory chapter
Biologyincluding the different types of tissues, their functions, and their locations.
BiologyNotes describing energy flow in ecosystems
BiologyApp 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
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
Health
Algebra
Calculus 1
Algebra 1
Overige