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Katie Whitson
12/1/2025
Biology
Boyles Law And Breathing
1 / 8
How We Breathe
Breathing involves a coordinated dance between your ribs, diaphragm, and lungs. When you breathe in, your rib cage expands and your diaphragm tightens and moves downward. This causes your lungs to expand, creating more space for air to flow in.
When you breathe out, the opposite happens. Your diaphragm relaxes, moving upward while your rib cage shrinks. This squeezes your lungs, forcing air out of your body.
Try This! Place your hand on your stomach and take a deep breath. Feel how your diaphragm pushes outward when you inhale and moves inward when you exhale.
Breathing Rates and Boyle's Law
Your breathing rate changes throughout your life. Newborns breathe 35-40 times per minute, while adults typically breathe only 12-20 times per minute. This difference happens because as we grow, our lungs become more efficient.
Boyle's Law explains what happens inside our lungs when we breathe. This scientific principle states that when the volume of a gas increases, its pressure decreases (assuming temperature stays the same). Our lungs use this relationship between pressure and volume to draw air in and push it out.
Each breath exchanges carbon dioxide (waste gas) for oxygen (gas we need to live). Without this constant exchange, our cells couldn't function properly.
The Science Behind Breathing
Boyle's Law shows that pressure and volume have an inverse relationship - when one goes up, the other goes down. This is exactly what happens in our lungs during breathing!
Our respiratory system includes the windpipe (trachea), which branches into tubes called bronchi that lead to tiny air sacs called alveoli. These alveoli are where oxygen enters our bloodstream and carbon dioxide exits.
The diaphragm is the star player in breathing. When it contracts and moves down, it creates more space in the chest cavity, increasing lung volume and decreasing pressure inside them.
Amazing Fact: Your lungs contain about 300 million alveoli, giving them a total surface area roughly the size of a tennis court!
How Lungs Expand and Contract
Your lungs are made of spongy, elastic tissue that can stretch and shrink. This elasticity is crucial for breathing. When your diaphragm moves downward, it increases the volume inside your chest cavity, causing your lungs to expand.
As lung volume increases, the pressure inside decreases (following Boyle's Law). This lower pressure inside your lungs compared to the outside air pressure causes air to rush in - that's an inhalation!
When your diaphragm relaxes and moves upward, lung volume decreases and pressure increases, pushing air out - that's an exhalation. This continuous cycle keeps your body supplied with oxygen and removes carbon dioxide.
Applying Boyle's Law to Inhalation
When you inhale, your diaphragm contracts and moves down while your rib cage expands. This increases the volume inside your chest cavity, which according to Boyle's Law, decreases the air pressure inside your lungs.
Since air naturally flows from areas of high pressure to areas of low pressure, air rushes into your lungs through your nose and mouth. This is how you breathe in!
When you exhale, the opposite occurs. Your diaphragm relaxes and moves up, decreasing lung volume and increasing pressure inside your lungs. This higher pressure pushes air out of your lungs.
Think About It: Your breathing is basically air responding to pressure differences, not your body "sucking in" air!
When Breathing Gets Knocked Out
Ever had the "wind knocked out of you"? This happens when a sudden blow to your abdomen forces your diaphragm to spasm. When your abdomen gets hit, your diaphragm rapidly moves upward.
This sudden movement drastically decreases lung volume while simultaneously increasing pressure inside the lungs. According to Boyle's Law, this pressure spike forces air out rapidly.
The diaphragm spasm temporarily prevents normal breathing movements, making it difficult to inhale. Don't worry though - the diaphragm usually relaxes within a minute or two, allowing normal breathing to resume.
Emphysema and Boyle's Law
Emphysema is a lung condition where the alveoli (tiny air sacs) lose their elasticity and become permanently enlarged. This might seem like a good thing - bigger lungs! - but it actually causes serious breathing problems.
When lung tissue loses elasticity, the pressure-volume relationship is disrupted. Enlarged alveoli can't contract efficiently during exhalation, which means they can't generate enough pressure to push air out completely.
This leads to air becoming trapped in the lungs. According to Boyle's Law, without proper pressure changes, the normal flow of air becomes difficult. People with emphysema often struggle to breathe out, which then makes breathing in harder too.
Health Note: Smoking is the leading cause of emphysema, damaging lung tissue over time and reducing its elasticity.
Boyle's Law and Scuba Diving Safety
Scuba divers are taught never to hold their breath while ascending from deep water - and Boyle's Law explains why this is dangerous. As a diver descends, water pressure increases, compressing the air in their lungs.
If a diver holds their breath while ascending, the decreasing water pressure allows the compressed air to expand rapidly (following Boyle's Law). This sudden expansion can overinflate and potentially rupture lung tissue - a serious condition called pulmonary barotrauma.
The proper technique is to breathe normally or exhale slowly while ascending. This allows the expanding air to escape safely rather than putting dangerous pressure on lung tissue.
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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
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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.
Samantha Klich
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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
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
How Boyle's Law Influences Breathing
Ever wondered why your lungs fill with air when you breathe in? The secret lies in Boyle's Law - a scientific principle that explains the relationship between gas pressure and volume. This fascinating connection helps us understand how our bodies... Show more
How We Breathe
Breathing involves a coordinated dance between your ribs, diaphragm, and lungs. When you breathe in, your rib cage expands and your diaphragm tightens and moves downward. This causes your lungs to expand, creating more space for air to flow in.
When you breathe out, the opposite happens. Your diaphragm relaxes, moving upward while your rib cage shrinks. This squeezes your lungs, forcing air out of your body.
Try This! Place your hand on your stomach and take a deep breath. Feel how your diaphragm pushes outward when you inhale and moves inward when you exhale.
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
Breathing Rates and Boyle's Law
Your breathing rate changes throughout your life. Newborns breathe 35-40 times per minute, while adults typically breathe only 12-20 times per minute. This difference happens because as we grow, our lungs become more efficient.
Boyle's Law explains what happens inside our lungs when we breathe. This scientific principle states that when the volume of a gas increases, its pressure decreases (assuming temperature stays the same). Our lungs use this relationship between pressure and volume to draw air in and push it out.
Each breath exchanges carbon dioxide (waste gas) for oxygen (gas we need to live). Without this constant exchange, our cells couldn't function properly.
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
The Science Behind Breathing
Boyle's Law shows that pressure and volume have an inverse relationship - when one goes up, the other goes down. This is exactly what happens in our lungs during breathing!
Our respiratory system includes the windpipe (trachea), which branches into tubes called bronchi that lead to tiny air sacs called alveoli. These alveoli are where oxygen enters our bloodstream and carbon dioxide exits.
The diaphragm is the star player in breathing. When it contracts and moves down, it creates more space in the chest cavity, increasing lung volume and decreasing pressure inside them.
Amazing Fact: Your lungs contain about 300 million alveoli, giving them a total surface area roughly the size of a tennis court!
Sign up to see the contentIt's free!
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
How Lungs Expand and Contract
Your lungs are made of spongy, elastic tissue that can stretch and shrink. This elasticity is crucial for breathing. When your diaphragm moves downward, it increases the volume inside your chest cavity, causing your lungs to expand.
As lung volume increases, the pressure inside decreases (following Boyle's Law). This lower pressure inside your lungs compared to the outside air pressure causes air to rush in - that's an inhalation!
When your diaphragm relaxes and moves upward, lung volume decreases and pressure increases, pushing air out - that's an exhalation. This continuous cycle keeps your body supplied with oxygen and removes carbon dioxide.
Sign up to see the contentIt's free!
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Applying Boyle's Law to Inhalation
When you inhale, your diaphragm contracts and moves down while your rib cage expands. This increases the volume inside your chest cavity, which according to Boyle's Law, decreases the air pressure inside your lungs.
Since air naturally flows from areas of high pressure to areas of low pressure, air rushes into your lungs through your nose and mouth. This is how you breathe in!
When you exhale, the opposite occurs. Your diaphragm relaxes and moves up, decreasing lung volume and increasing pressure inside your lungs. This higher pressure pushes air out of your lungs.
Think About It: Your breathing is basically air responding to pressure differences, not your body "sucking in" air!
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
When Breathing Gets Knocked Out
Ever had the "wind knocked out of you"? This happens when a sudden blow to your abdomen forces your diaphragm to spasm. When your abdomen gets hit, your diaphragm rapidly moves upward.
This sudden movement drastically decreases lung volume while simultaneously increasing pressure inside the lungs. According to Boyle's Law, this pressure spike forces air out rapidly.
The diaphragm spasm temporarily prevents normal breathing movements, making it difficult to inhale. Don't worry though - the diaphragm usually relaxes within a minute or two, allowing normal breathing to resume.
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
Emphysema and Boyle's Law
Emphysema is a lung condition where the alveoli (tiny air sacs) lose their elasticity and become permanently enlarged. This might seem like a good thing - bigger lungs! - but it actually causes serious breathing problems.
When lung tissue loses elasticity, the pressure-volume relationship is disrupted. Enlarged alveoli can't contract efficiently during exhalation, which means they can't generate enough pressure to push air out completely.
This leads to air becoming trapped in the lungs. According to Boyle's Law, without proper pressure changes, the normal flow of air becomes difficult. People with emphysema often struggle to breathe out, which then makes breathing in harder too.
Health Note: Smoking is the leading cause of emphysema, damaging lung tissue over time and reducing its elasticity.
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
Boyle's Law and Scuba Diving Safety
Scuba divers are taught never to hold their breath while ascending from deep water - and Boyle's Law explains why this is dangerous. As a diver descends, water pressure increases, compressing the air in their lungs.
If a diver holds their breath while ascending, the decreasing water pressure allows the compressed air to expand rapidly (following Boyle's Law). This sudden expansion can overinflate and potentially rupture lung tissue - a serious condition called pulmonary barotrauma.
The proper technique is to breathe normally or exhale slowly while ascending. This allows the expanding air to escape safely rather than putting dangerous pressure on lung tissue.
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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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