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059 An Introduction to the Respiratory System

We are off to start learning from a new set of videos about another part of the human body system and here, Leslie opens a new topic with a brief introduction of the Respiratory System.

Watch and enjoy!

Transcript of Today’s Episode

Hello and welcome to another episode of Interactive-Biology T.V. where we’re making Biology fun! My name is Leslie Samuel and in this episode, Episode 59, I’m going to be giving an introduction to the respiratory system. So, we’re changing gears now. We just finished talking about the circulatory system and, now, we’re going to talk about a system that is very closely linked to the circulatory system that is, the respiratory system.

So, let’s get right into it. Here, we’re looking at a bunch of ladies. These ladies are exercising. They are working out in the gym. Some of them are on the, like over here you can see we have one on an elliptical then, we have some riding exercise, bikes and lifting some dumbbells here and boxing a punching bag, punching a punching bag and there’s a lot going on right here. There’s one thing that these ladies all have in common, well, there are a number of things that these ladies have in common. They’re all attractive that’s one. They’re all exercising but, the thing that I want to focus on is that they are all breathing. I hope that make sense. They are all breathing, they are working out and in order to be able to get the energy that they need, they need to be breathing in oxygen. There are a number of things that have to happen in that process and we are going to talk about that today. So, whether you’re exercising or you’re just standing still or even if you are sleeping, you need to be breathing if you’re going to be alive of course, and we’re going to be talking about that today. So, let’s get right into it.

In order for us to have energy, there is a process that needs to happen and this process is called, ‘cellular respiration.’ Now, we’re not going to go into too much detail in terms of cellular respiration in this episode but, we are going to come back to it. The main thing that I want us to look at is the formula for cellular respiration, and that formula is:


If you’re a biologist, you’re into Biology, you’re in a Biology class, or whatever the case might be, I think, it’s imperative for you to know this formula. So, memorize this formula:


Now, let’s give some names to these bad boys. This guy over here (C6H12O6), that is none other glucose, okay so that a carbohydrate, it’s a type of sugar. O2, you should know that is oxygen. And then, of course CO2 is carbon dioxide and H2O, if you don’t know this, something is wrong, that is water. Well, maybe nothing is wrong, maybe you just never heard of it before. But, anyhow so, we have glucose that’s reacting with oxygen and the products, so these are the reactants on the left, the products on the right are carbon dioxide and water. And this right here is the general equation for cellular respiration. It is an oversimplification but, it gives you the things that are necessary and the things that are produced. Now, glucose, where do we get this from? Well, of course, we eat, right? We take in some food and we get glucose. So, let’s say we get this (glucose) from eating, oxygen, we get this from breathing, there’s oxygen in the air and, when we breathe, we bring in that oxygen that we need. Carbon dioxide, this is actually a waste product. We’re producing this but, we don’t actually use it. When we breathe, we breathe that out and that goes into the air, and that’s used by plants and plants can use that for photosynthesis. Water, do we need water? Yes, of course we need water. I’m not going to write anything right here because it’s just water. Water is essential for life and we are actually producing water in this process of cellular respiration.

In doing this entire thing, one of the things that we are making, or the main thing that we are making is energy. But, in order to make that energy, in order for us to get that energy when we’re exercising, walking, whatever we’re doing, we need to have oxygen. This oxygen needs to come in and, this is why we are breathing in, we’re taking in the air, and in the air, there is oxygen. And of course, we need to get rid of the carbon dioxide so, when we breathe that out, that is getting rid of the carbon dioxide. It’s doing some other things but, this the main function, the main functions of the respiratory system. We want to take the good stuff in, which in this case is the oxygen, and we want to take the bad stuff out, which in this case would be carbon dioxide. So, memorize this equation if you haven’t already, know what the components are and where they come from.

Let’s continue now. We’ve been looking at the circulatory system and, we’ve looked at over here, we have the heart and that heart is very important because it allows us to circulate the blood through our circulatory system and, one of the things that the heart does before it sends blood to the body is it sends the blood to the lungs. You can see here that the pulmonary vein is going away from the heart and that takes blood to the lungs, this is the lungs right here, and then, that blood takes up oxygen and comes back to the left ventricle and the left ventricle then pumps the blood via the aorta to the rest of the body. We’ve looked at that in previous episodes. If you do not remember, you can visit the section that’s right before this and you will get a review on that.

Now, what we’re going to do here, this is looking at the lungs but, it’s not looking at the lungs in detail. So, what we’re going to do is come over to this guy over here which is not showing the circulatory system but, it’s showing the respiratory system. And, you can see here we have the lungs and then, we have the mouth here, the oral cavity, which then goes into the pharynx and then, to the trachea and then, that takes us to the bronchus and the bronchioles and then, that goes into alveoli, and then, we can take this section here and you can see a larger area of the alveoli.

Not only that, we don’t only breathe in through our mouth, we also breathe in through our nose and, you can see the nasal cavity here is also leading into the pharynx which then goes the same route via the trachea and so on and so forth.

And, what I want you to notice is that when we look at this small section and, we look here at the alveoli, you can see that the pulmonary vein is coming in and then, it’s forming these capillary beds, and then, you can see the pulmonary artery is then going out. I want you to also notice the colors. Here, it’s showing red and this is when there’s no oxygen in the blood but as it comes into the capillary beds, and we are breathing in the air that’s coming in through the trachea, and the bronchus and the bronchioles to the alveoli, you can see here that when the oxygen gets in here, that can then go into the capillary beds and you see this color changing from red to kind of purplish and then to blue because it’s taking up that oxygen and then, that oxygenated blood is going via that pulmonary artery back to the heart.

There’s another thing that I want to mention here because I’m just giving an introduction so we’re going to go into more detail and all of these aspects later but, here we have the diaphragm, which is a muscle, and there are other muscles that are involved, and when those muscles contract, it causes the lungs to expand and, we breathe in air that has oxygen. The oxygen then gets taken into the blood stream and that goes back to the heart and the heart can then pump that oxygenated blood through the rest of the body.

Not only that, but, as the blood comes to the alveoli, it’s also bringing with it carbon dioxide. Remember that carbon dioxide that we made in cellular respiration, that’s bringing that carbon dioxide. That carbon dioxide can then go into the alveoli and then, when we breathe out, that carbon dioxide comes out via the alveoli and through the bronchioles and the bronchus and the trachea and then, through the pharynx and then either through the oral cavity or the nasal cavity.

So, we’re getting that bad stuff out, we’re getting the good stuff in. That is what the respiratory system is all about.

So, there you have it. That’s just kind of a brief overview. I kind of glossed over a lot of the details because I’m going to be getting into those details in future episodes.

But, for right now, I want to invite you to visit Interactive-Biology.com and, you will find more Biology videos, quizzes, games, a whole bunch of resources, you want to check them out. So, that’s it for this video and, and I’ll see you on the next one.

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Leslie Samuel is the creator of Interactive Biology. His mission is to use this site to Make Biology fun for people all over the world.

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Leave An AWESOME Comment

55 Responses to “059 An Introduction to the Respiratory System”

  1. Ricoytobias June 10, 2011 at 4:38 am #

    A little correction though to the video. When your talking about the PULMONARY VEINS & PULMONARY ARTERIES, it is actually contrast to what your explaining about. PULMONARY ARTERIES are actually the BLUE ones which carries deoxygenated (Carbon dioxide concentrated/Less oxygen) blood,and the “RED” one is actually the PULMONARY VEINS, it is the only vein that carries OXYGENATED (Oxygen rich) blood in our body…. just a quick correction on that bro, no offense.. ;) Great Vid..

    -Ric

    • Miranda March 11, 2012 at 7:35 pm #

      Veins do NOT carry oxygen. That’s why when you want to see how much oxygen is in your blood, you do an arterial stick. I’m sorry, but you’re wrong. Veins do NOT contain oxygen, only arteries contain oxygen. I’m in A&P II right now and my instructor is a Physician, and she knows what she’s talking about, and that is what my book says as well. So, pulmonary VEINS are blue, all veins are blue, and all arteries are red. Do some research and get back to us on that.

      • Miranda March 11, 2012 at 7:40 pm #

        Nevermind, I jumped the gun, I am wrong. My apologies….if my post can be deleted, that would be great!

        • Leslie Samuel March 12, 2012 at 12:01 am #

          I don’t typically delete comments unless they are offensive. I’m not offended :)

      • Leslie Samuel March 12, 2012 at 12:00 am #

        You should make your own youtube videos Miranda ;)

      • gracia March 14, 2012 at 10:40 pm #

        sorry but they do contain oxygen apart from the pulmonary veins which carry deoxygenated blood.the rest of the veins carry oxygenated blood. reason to why respiration system in the muscle contraction produces oxygen to be supplied to to many tissues in the muscles which are carried by the ventricles and then to so may capillaries which are small types of arteries initially all veins carry oxygenated blood apart from the pulmonary vein. Just check how blood is transport through your heart and you will understand. his right

      • safar September 17, 2013 at 10:29 am #

        veins are taking DO2 blood from all the body to the atrium and ventrical and artries taking O2 nated blood from heart to all body but just pulmonarry artery carry dioxigrnated blood from right ventrical to lungs blood after taking O2 by hemoglobin it carry to pulmonarry veins and left ventrical.

      • Basem June 16, 2014 at 3:08 pm #

        Veins and venules carry blood towards the heart, whereas arteries and arterioles carry blood away from the heart. Those are the definitions.

        He has mixed them up in this video, as he is possibly defining arteries and veins in terms of the oxygenation of blood rather than direction of blood flow relative to the heart. The pulmonary arteries are shown blue as the blood (coming from the right ventricle and by extension the systemic veins) is deoxygenated, whereas the pulmonary veins carry oxygenated blood (red).

        Extra: The red/blue colour stems from the fact that deoxygenated blood (in our systemic veins) appear blue underneath our skin. The colour is actually a dark red, but appears blue through our skin.

  2. Ricoytobias June 10, 2011 at 8:38 am #

    A little correction though to the video. When your talking about the PULMONARY VEINS & PULMONARY ARTERIES, it is actually contrast to what your explaining about. PULMONARY ARTERIES are actually the BLUE ones which carries deoxygenated (Carbon dioxide concentrated/Less oxygen) blood,and the “RED” one is actually the PULMONARY VEINS, it is the only vein that carries OXYGENATED (Oxygen rich) blood in our body…. just a quick correction on that bro, no offense.. ;) Great Vid..

    -Ric

  3. InteractiveBiology June 10, 2011 at 8:51 am #

    @Ricoytobias Wow, can’t believe I missed that one. Arteries go away from the heart, veins go towards the heart. Thanks for the correction. Will see how I can correct that. Maybe with a follow up video. Thanks!

  4. InteractiveBiology June 10, 2011 at 8:51 am #

    Wow, can’t believe I missed that one. Arteries go away from the heart, veins go towards the heart. Thanks for the correction. Will see how I can correct that. Maybe with a follow up video. Thanks!

  5. InteractiveBiology June 10, 2011 at 12:51 pm #

    Wow, can’t believe I missed that one. Arteries go away from the heart, veins go towards the heart. Thanks for the correction. Will see how I can correct that. Maybe with a follow up video. Thanks!

  6. Ricoytobias June 15, 2011 at 6:42 pm #

    @InteractiveBiology – Yeah, Arteries = away from the heart, Veins = Towards the heart. But the difference in this one is PULMONARY veins = oxygen rich, PULMONARY arteries = oxygen poor. Thanks buddy, hope you continue making videos. We really appreciated it

  7. Ricoytobias June 15, 2011 at 6:42 pm #

    – Yeah, Arteries = away from the heart, Veins = Towards the heart. But the difference in this one is PULMONARY veins = oxygen rich, PULMONARY arteries = oxygen poor. Thanks buddy, hope you continue making videos. We really appreciated it

  8. Ricoytobias June 15, 2011 at 6:42 pm #

    – Yeah, Arteries = away from the heart, Veins = Towards the heart. But the difference in this one is PULMONARY veins = oxygen rich, PULMONARY arteries = oxygen poor. Thanks buddy, hope you continue making videos. We really appreciated it

  9. Ricoytobias June 15, 2011 at 10:42 pm #

    - Yeah, Arteries = away from the heart, Veins = Towards the heart. But the difference in this one is PULMONARY veins = oxygen rich, PULMONARY arteries = oxygen poor. Thanks buddy, hope you continue making videos. We really appreciated it

  10. RochelleHansonMusic June 28, 2011 at 9:54 am #

    This is pretty cool :) I’m gonna share his with my group…. Before it becomes a page lol har har har inside joke ;)

  11. InteractiveBiology June 28, 2011 at 10:02 am #

    @RochelleHansonMusic LOL. Good one Rochelle. That made me laugh!

  12. InteractiveBiology June 28, 2011 at 10:02 am #

    LOL. Good one Rochelle. That made me laugh!

  13. RochelleHansonMusic June 28, 2011 at 1:54 pm #

    This is pretty cool :) I’m gonna share his with my group…. Before it becomes a page lol har har har inside joke ;)

  14. InteractiveBiology June 28, 2011 at 2:02 pm #

    LOL. Good one Rochelle. That made me laugh!

  15. SanderSpook January 23, 2012 at 4:12 pm #

    This became my favorite episode after 0:30 seconds :) although I initially had some difficulty keeping my attention, your explanation got me through it.

    Thumbs up and high five for your channel!

  16. SanderSpook January 23, 2012 at 9:12 pm #

    This became my favorite episode after 0:30 seconds :) although I initially had some difficulty keeping my attention, your explanation got me through it.

    Thumbs up and high five for your channel!

  17. James January 24, 2012 at 7:43 pm #

    Been watching all your clips and I wonder why my lecturers cant be as good at teaching as you are! Your a Legend

    • Lrsamuel January 24, 2012 at 9:58 pm #

      Well thank you James.

      I appreciate the compliment ;)

  18. janiewoodsie March 17, 2012 at 7:53 am #

    Very misleading video. Completely the wrong way round – blue capillaries have picked up oxygen?!? Etc etc. Please correct this ASAP so that I can recommend it to my students. Some of your other videos are very useful in my biology classes.

  19. janiewoodsie March 17, 2012 at 11:53 am #

    Very misleading video. Completely the wrong way round – blue capillaries have picked up oxygen?!? Etc etc. Please correct this ASAP so that I can recommend it to my students. Some of your other videos are very useful in my biology classes.

  20. dennisrayso March 21, 2012 at 7:09 pm #

    explain the joke to me please

  21. kevynsken April 1, 2012 at 10:33 pm #

    Wow! I’m new to Mr. Samuel’s videos. He’s very good but no one is perfect. There is a better way for you to phrase that. Your responsibility to your students is yours alone. Be appreciative of the time and effort others put into to making your job that much easier. Otherwise, consider making your own videos for your students ASAP.

  22. kevynsken April 2, 2012 at 2:33 am #

    Wow! I’m new to Mr. Samuel’s videos. He’s very good but no one is perfect. There is a better way for you to phrase that. Your responsibility to your students is yours alone. Be appreciative of the time and effort others put into to making your job that much easier. Otherwise, consider making your own videos for your students ASAP.

  23. norcoboy April 16, 2012 at 6:10 pm #

    Eschuchela, la ciudad respirando

  24. norcoboy April 16, 2012 at 10:10 pm #

    Eschuchela, la ciudad respirando

  25. digiconvalley April 21, 2012 at 8:29 pm #

    pulmonary artery takes the deoxygenated blood, ryt? i always get confused

  26. digiconvalley April 21, 2012 at 8:34 pm #

    didnt u say opposite? i thot when its red, it has oxygen.. blue colour shows the deoxygenated blood..

  27. digiconvalley April 21, 2012 at 8:37 pm #

    oh I am sorry, i didnt see the first comment on this video.. btw u are an awesome teacher, i wish u were my biology teacher, all the other videos are rocking too

  28. digiconvalley April 22, 2012 at 12:29 am #

    pulmonary artery takes the deoxygenated blood, ryt? i always get confused

  29. digiconvalley April 22, 2012 at 12:34 am #

    didnt u say opposite? i thot when its red, it has oxygen.. blue colour shows the deoxygenated blood..

  30. digiconvalley April 22, 2012 at 12:37 am #

    oh I am sorry, i didnt see the first comment on this video.. btw u are an awesome teacher, i wish u were my biology teacher, all the other videos are rocking too

  31. MrBleather June 9, 2012 at 4:12 am #

    Your amazing!! Keep up the great videos. You have helped me learn what I need to know for my exams. Would have got discouraged and failed without you.

  32. MrBleather June 9, 2012 at 4:12 am #

    Your amazing!! Keep up the great videos. You have helped me learn what I need to know for my exams. Would have got discouraged and failed without you.

  33. tc June 18, 2012 at 8:03 am #

    Let me guess…Miranda must be the blonde girl in the clip at the start of this tutorial! LOL xx

  34. melanie August 21, 2012 at 10:22 am #

    A bit degrading to say look at these women see see,,,with their breast being all over the place. Video starts off very condescending and exploitive to women (inhumane close to pornography). I’d appreciate more respectable videos, obviously this speaker is from the hood.

  35. emullen93 November 5, 2012 at 5:57 am #

    OHHHH YEAH. that elliptical girl

  36. artem bluntzki February 4, 2013 at 1:23 am #

    haha, funny video

  37. Daniel Chavez Moran April 8, 2013 at 6:04 pm #

    Nice post. I learn something totally new and challenging on websites I stumbleupon on a daily basis.
    It will always be helpful to read through content from other authors and use a little something from their web sites.

  38. Saternoc May 1, 2013 at 11:53 am #

    Glad I read your comment before watching the video. That way I never got confused and kept that important concept in mind.

  39. yogayantra Dominique May 12, 2013 at 2:01 pm #

    Thanks Leslie, I really appreciate your teaching. Very useful, clear!

  40. Yvette June 17, 2013 at 8:32 pm #

    I signed up for your lessons as a teacher however, I teach at an all male high school and this Respiratory Video is problematic.
    You start with images of women at the gym and the most obvious thing any hormonal boy will focus on is the direct shot of the boobs of the woman on the spin cycle. Are you aware of this? I cannot imagine why you wouldn’t have considered this as possibly a problem. For this reason I would not be able to show your video to my students. This is a shame. I’m hoping that you might consider your audience and use more gender neutral images.
    Thank you.

  41. dominique July 5, 2013 at 3:33 am #

    Hi Samuel, I quite like your episodes, but have you heard about the Buteyko Method? If not, please fill a lack, because it is a very important way of breathing that heals dozens of conditions and thousands of patient. One thing i learnt is: CARBON DIOXYDE IS NOT A WASTE PRODUCT. We need it for a lot of biological processes in our body. It’s been a widespread mistake, in particular in the field of yoga, to want to “eliminate” CO2 as if this gas was toxic. We need it. http://www.youtube.com/watch?v=eR1JlRA6_v4 is one of the many links that might be of interest! Thank you

  42. Faddy Gee August 2, 2013 at 6:25 pm #

    They have alot in common…they’re all attractive LOL

  43. Ghandy Chavez October 8, 2013 at 4:04 am #

    First time in your channels and this is awesome I’ll defiantly check and hear more from you thank you

  44. Cindy November 17, 2013 at 7:23 pm #

    I thought pulmonary veins (deoxy blood) go to the heart and pulmonary arteries (oxy blood ) go away from the heart. Is this correct?

    • maria March 4, 2014 at 12:46 pm #

      yes he said it wrong.

  45. Jacqueline April 14, 2014 at 7:39 pm #

    You said the part about the pulmoary veins and arteries wrong. The blue is deoxy blood in the pulmonary arteries that came from the heart, this goes to the alveoli and gets oxygenated which is the red blood in the pulmonary veins going to the heart. Should probably fix that as it is a key factor

  46. mariyana June 28, 2014 at 6:08 am #

    Hey Samuel,
    Just wanted to say thank you for the great videos that u make.
    I study in the university and u r explaining this stuff better than my teachers does!!!
    We r enjoying ur videos here in Israel too… Big appreciation and love from Israel..
    Thank u very much, hope u continue making such a great videos! :)

    P.S.
    Like everybody else here I was confused with the issue of pulmonary arteries and veins and the oxygenated blood. I think that mentioning the comment that u wrote in the comments about how arteries goes from the heart and the veins to the heart, and reviewing the circulatory system a little bit, could prevent some of the mean comment in here.
    Now I understand everything better.

    Tnx again for the great videos, u r the best!!!