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Jan 15, 2026
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Understanding the Respiratory System: Anatomy, Functions, and Common Conditions
Lia Ventura
@cookiesgood_aktq
1 / 5
Respiratory System Basics
The respiratory system has two main jobs: delivering oxygen to your body and removing carbon dioxide waste. When you breathe, you're performing ventilation - the process of moving air in and out of your lungs.
Your respiratory system does more than just breathing. It filters, warms, and humidifies air through mucous membranes. It helps you speak, allows you to smell (olfaction), and plays a role in maintaining your body's balance (homeostasis).
Respiration happens in two important phases. External respiration occurs when oxygen moves from your nose to your lungs' air sacs. Internal respiration happens when oxygen from your bloodstream enters your body tissues and carbon dioxide waste is collected.
Fun Fact: Each time you breathe, air travels through a complex pathway designed to protect your lungs and maximize oxygen absorption!
The upper respiratory tract includes your nasal cavity (with nostrils or nares), where tiny hair-like structures called cilia trap particles in mucus. Your nasal cavity is divided by the septum, and the palate separates your nose from your mouth cavity.
The Throat and Lungs
The pharynx (throat) has three sections: nasopharynx, oropharynx, and laryngopharynx. Your uvula hangs from the soft palate, and the epiglottis is a critical flap that covers your windpipe when you swallow to prevent choking. The tonsils help filter out harmful particles.
Your larynx (voice box) contains your vocal cords and marks the division between upper and lower airways. Below this sits the trachea (windpipe), a rigid tube supported by C-shaped rings of cartilage. The trachea branches into left and right bronchial trees that lead to your lungs.
Your lungs are protected by the pleura - two layers of membrane with fluid between them to prevent friction. The right lung has three lobes while the left has only two (making space for your heart). Inside your lungs, bronchi divide into smaller bronchioles that end in tiny air sacs called alveoli.
Remember This: Oxygen transfer happens in the alveoli, which are surrounded by capillaries. This is where your respiratory and circulatory systems work together!
The diaphragm is your primary breathing muscle. When you inhale, it contracts and flattens, creating more space in your chest for your lungs to expand. When you exhale, it relaxes and moves upward, helping push air out of your lungs.
Respiratory Exchange and Age-Related Changes
The respiratory exchange process is remarkable. Oxygen enters your alveoli and passes through their thin walls into nearby capillaries. Meanwhile, carbon dioxide waste moves from your blood into the alveoli to be exhaled. This exchange happens billions of times throughout your life!
As we age, normal senescent changes occur in the respiratory system. Your rib cage becomes less flexible, lung elasticity decreases, and respiratory muscles weaken. These natural changes explain why older adults might have reduced breathing capacity.
Abnormal oxygen levels can cause serious problems. Hypoxia means low oxygen, anoxia means no oxygen, and asphyxia refers to insufficient oxygen intake from any cause. Asphyxia can be physical (like suffocation) or chemical (like carbon monoxide poisoning).
Health Alert: Your cough reflex is actually a protective mechanism that helps clear mucus from your airways to improve gas exchange!
Your respiratory system relies on several groups of muscles to help with breathing. Besides your diaphragm, you have accessory respiratory muscles in your neck, between your ribs (intercostal), and in your abdomen that assist with breathing, especially during exercise.
Common Respiratory Conditions
Upper respiratory infections are familiar to most of us. The common cold is caused by rhinoviruses, while conditions like rhinitis (inflamed nose), pharyngitis (sore throat), and laryngitis (voice loss) affect specific parts of your upper airways. Children often experience croup with its distinctive barking cough.
Lower respiratory problems can be more serious. Acute bronchitis inflames the airways and can lead to pneumonia. Pneumonia itself is an infection in the lungs that can be either viral or bacterial.
Chronic Obstructive Pulmonary Disease (COPD) includes several long-term conditions that block airflow. Asthma causes airways to constrict and produce excess mucus in response to triggers like allergens or cold air. Treatment includes bronchodilators to open airways and steroids to reduce inflammation.
Did You Know? Many respiratory conditions can be prevented or managed with simple steps like avoiding tobacco smoke, getting vaccinated, and practicing good hand hygiene!
Emphysema damages the alveoli, making them lose elasticity, while chronic bronchitis causes persistent coughing due to inflamed airways. Both are forms of COPD often linked to smoking or environmental exposures. Tuberculosis (TB) is a bacterial infection that primarily affects the lungs but can spread to other parts of the body.
Other Respiratory Conditions
The respiratory system faces many challenges beyond common infections. Pleurisy involves inflammation of the pleura (the lung's protective membrane), causing sharp chest pain with breathing. Atelectasis occurs when part or all of a lung collapses.
Breathing in harmful particles causes various types of pneumoconiosis, including silicosis (from silica dust), anthracosis (from coal dust), and asbestosis (from asbestos fibers). These occupational lung diseases develop after years of exposure and can cause permanent damage.
Respiratory conditions often affect your body's acid-base balance. Respiratory acidosis happens when too much carbon dioxide builds up in your blood, decreasing pH (common in emphysema). Respiratory alkalosis occurs when you lose too much carbon dioxide through hyperventilation, raising blood pH.
Important: Your respiratory and circulatory systems work together so closely that problems in one often affect the other. For example, left-sided heart failure can cause pulmonary edema (fluid in the lungs).
Other serious conditions include pulmonary embolism (a blood clot traveling to the lungs) and lung cancer (malignant tumors). Many respiratory diseases can be prevented through lifestyle choices like avoiding smoking, using protective equipment in dusty environments, and getting regular check-ups.
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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❗️❗️⚠️
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homepage/newPositiveReviewText6
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
homepage/newPositiveReviewText6
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
Understanding the Respiratory System: Anatomy, Functions, and Common Conditions
Lia Ventura
@cookiesgood_aktq
The respiratory system is your body's lifeline, bringing in oxygen and removing carbon dioxide. This vital system includes both upper and lower airways that work together to keep every cell in your body functioning. Understanding how your respiratory system works... Show more
Respiratory System Basics
The respiratory system has two main jobs: delivering oxygen to your body and removing carbon dioxide waste. When you breathe, you're performing ventilation - the process of moving air in and out of your lungs.
Your respiratory system does more than just breathing. It filters, warms, and humidifies air through mucous membranes. It helps you speak, allows you to smell (olfaction), and plays a role in maintaining your body's balance (homeostasis).
Respiration happens in two important phases. External respiration occurs when oxygen moves from your nose to your lungs' air sacs. Internal respiration happens when oxygen from your bloodstream enters your body tissues and carbon dioxide waste is collected.
Fun Fact: Each time you breathe, air travels through a complex pathway designed to protect your lungs and maximize oxygen absorption!
The upper respiratory tract includes your nasal cavity (with nostrils or nares), where tiny hair-like structures called cilia trap particles in mucus. Your nasal cavity is divided by the septum, and the palate separates your nose from your mouth cavity.
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The Throat and Lungs
The pharynx (throat) has three sections: nasopharynx, oropharynx, and laryngopharynx. Your uvula hangs from the soft palate, and the epiglottis is a critical flap that covers your windpipe when you swallow to prevent choking. The tonsils help filter out harmful particles.
Your larynx (voice box) contains your vocal cords and marks the division between upper and lower airways. Below this sits the trachea (windpipe), a rigid tube supported by C-shaped rings of cartilage. The trachea branches into left and right bronchial trees that lead to your lungs.
Your lungs are protected by the pleura - two layers of membrane with fluid between them to prevent friction. The right lung has three lobes while the left has only two (making space for your heart). Inside your lungs, bronchi divide into smaller bronchioles that end in tiny air sacs called alveoli.
Remember This: Oxygen transfer happens in the alveoli, which are surrounded by capillaries. This is where your respiratory and circulatory systems work together!
The diaphragm is your primary breathing muscle. When you inhale, it contracts and flattens, creating more space in your chest for your lungs to expand. When you exhale, it relaxes and moves upward, helping push air out of your lungs.
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Respiratory Exchange and Age-Related Changes
The respiratory exchange process is remarkable. Oxygen enters your alveoli and passes through their thin walls into nearby capillaries. Meanwhile, carbon dioxide waste moves from your blood into the alveoli to be exhaled. This exchange happens billions of times throughout your life!
As we age, normal senescent changes occur in the respiratory system. Your rib cage becomes less flexible, lung elasticity decreases, and respiratory muscles weaken. These natural changes explain why older adults might have reduced breathing capacity.
Abnormal oxygen levels can cause serious problems. Hypoxia means low oxygen, anoxia means no oxygen, and asphyxia refers to insufficient oxygen intake from any cause. Asphyxia can be physical (like suffocation) or chemical (like carbon monoxide poisoning).
Health Alert: Your cough reflex is actually a protective mechanism that helps clear mucus from your airways to improve gas exchange!
Your respiratory system relies on several groups of muscles to help with breathing. Besides your diaphragm, you have accessory respiratory muscles in your neck, between your ribs (intercostal), and in your abdomen that assist with breathing, especially during exercise.
Sign up to see the contentIt's free!
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Common Respiratory Conditions
Upper respiratory infections are familiar to most of us. The common cold is caused by rhinoviruses, while conditions like rhinitis (inflamed nose), pharyngitis (sore throat), and laryngitis (voice loss) affect specific parts of your upper airways. Children often experience croup with its distinctive barking cough.
Lower respiratory problems can be more serious. Acute bronchitis inflames the airways and can lead to pneumonia. Pneumonia itself is an infection in the lungs that can be either viral or bacterial.
Chronic Obstructive Pulmonary Disease (COPD) includes several long-term conditions that block airflow. Asthma causes airways to constrict and produce excess mucus in response to triggers like allergens or cold air. Treatment includes bronchodilators to open airways and steroids to reduce inflammation.
Did You Know? Many respiratory conditions can be prevented or managed with simple steps like avoiding tobacco smoke, getting vaccinated, and practicing good hand hygiene!
Emphysema damages the alveoli, making them lose elasticity, while chronic bronchitis causes persistent coughing due to inflamed airways. Both are forms of COPD often linked to smoking or environmental exposures. Tuberculosis (TB) is a bacterial infection that primarily affects the lungs but can spread to other parts of the body.
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Improve your grades
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By signing up you accept Terms of Service and Privacy Policy
Other Respiratory Conditions
The respiratory system faces many challenges beyond common infections. Pleurisy involves inflammation of the pleura (the lung's protective membrane), causing sharp chest pain with breathing. Atelectasis occurs when part or all of a lung collapses.
Breathing in harmful particles causes various types of pneumoconiosis, including silicosis (from silica dust), anthracosis (from coal dust), and asbestosis (from asbestos fibers). These occupational lung diseases develop after years of exposure and can cause permanent damage.
Respiratory conditions often affect your body's acid-base balance. Respiratory acidosis happens when too much carbon dioxide builds up in your blood, decreasing pH (common in emphysema). Respiratory alkalosis occurs when you lose too much carbon dioxide through hyperventilation, raising blood pH.
Important: Your respiratory and circulatory systems work together so closely that problems in one often affect the other. For example, left-sided heart failure can cause pulmonary edema (fluid in the lungs).
Other serious conditions include pulmonary embolism (a blood clot traveling to the lungs) and lung cancer (malignant tumors). Many respiratory diseases can be prevented through lifestyle choices like avoiding smoking, using protective equipment in dusty environments, and getting regular check-ups.
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
homepage/newPositiveReviewText6
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
homepage/newPositiveReviewText6
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