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Health and medicine
Course: Health and medicine > Unit 1
Lesson 2: Respiratory system introductionThermoregulation in the lungs
Created by Patrick van Nieuwenhuizen.
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- So if the outer temperature is above 37°C, does panting become useless? How do dogs regulate their temperature then?(26 votes)
- It would become less useful, but panting would still dissipate heat from the dog's body because the exhalations during panting contain a very high amount of water vapor. Water has a high heat capacity and thus will carry a lot of heat away from the dog's body and it is released into the environment.(34 votes)
- I like to run outside but when it is winter time I sometimes have a hard time running because the outside air is very cold (around 15 degrees F). It becomes harder to breath and I have to stop more often. I understand that my body has to work harder to stay warm and that could be a reason. Is there a way to help my lungs become used to the cold air? Or tips on how I can continue to exercise outside in colder conditions?(17 votes)
- Inhaling through your nose and exhaling through your mouth can be helpful when exercising in cold weather. Your nose helps to warm and filter air which can prevent irritation in the back of your throat and can save your lungs some effort. You can exhale through your nose, but the video can show you that air being exhaled has already reached your body's core temperature. Therefore, it is less necessary to exhale back through your nose to prevent irritation, and filtering exhaled air is not really necessary, as the air is being expelled and not going to be used by your lungs again.(12 votes)
- Although we mainly breathe out warm air, we are also able to force out cold air. How do we explain this? Thanks!(7 votes)
- That makes sense. If you pucker your lips and measure the air temp 2 inches away, the air feels cold (because your air stream is pushing the cold outside air into a little gust). But 1/2 inch from your mouth, the air feels very warm and humid.(12 votes)
- How does dog's thermoregulation work if the outside temperature is equal or higher than 100 F?(6 votes)
- Dogs can produce sweat on areas not covered with fur, such as the nose and paw pads, to cool down - unlike humans who sweat almost everywhere.(2 votes)
- What is the use of yawning? Why can't you just breath more often?(2 votes)
- There are several reasons why...
One is that when we are bored or tired, we just don't breathe as deeply as we usually do. As this theory goes, our bodies take in less oxygen because our breathing has slowed. Therefore, yawning helps us bring more oxygen into the blood and move more carbon dioxide out of the blood.(4 votes)
- So if someone is suffering from hypothermia, do they take in less than 5L of air a minute in order to preserve body heat?(3 votes)
- I just got done with running and playing outside and sweating but I'm not breathing hard. What is wrong?(1 vote)
- If you exercise a frequently you may have built up enough fitness that just playing/running a bit won't necessarily get you out of breath. It's definitely not a thing to worry about and means your heart and lungs work well. Probably if you increase the intensity or length of your exercise you'll start breathing harder.(4 votes)
- So there is only one way the air can travel? It is either inhaling or exhaling. So does this mean that there aren't any air particulates that stay in the lungs for a while, they all get exhaled. Or does some particles stay in the lungs?(1 vote)
- Yes. Some particulates that are able to avoid air filtration through the nose and travel down into the lungs can stay there for some time. However, special leukocytes (white blood cells) called macrophages can reach the alveoli where these particles are and phagocytose ("eat") them. They then travel to the bottom of the trachea, where ciliated cells push them to the top of the throat. Finally, they can be spat out or swallowed.
Other substances such as tar from cigarette smoke can also stick around in the lungs. This is what causes smokers' lungs to appear black.
Hope this helped!(3 votes)
- What do alveoli do and where do these live?(2 votes)
- Alveoli are little sacks that live in your lungs and allow the lungs to exchange oxygen for carbon dioxide in the blood.(1 vote)
- If we breath in cold air we usually breath out air with steam . what is the mechanism of the lung in that case ??(2 votes)
- When you exhale when it's cold outside, the water vapor in your breath condenses into lots of tiny droplets of liquid water and ice (solid water) that you can see in the air as a cloud, similar to fog.(1 vote)
Video transcript
Voiceover: If you have a
dog or if ever played fetch with a dog, you've probably noticed that after you've really
abused that poor animal and run it into the ground,
you've probably noticed that it started to do
something interesting. It started panting. Did you ever stop to ask
yourself why dogs pant? Well, here's your chance
to answer that question. See if you could come up with a reason. It turns out that the main reason that dogs pant is so they don't overheat. Let's take a look at how that works. Let's say here we've got
our favorite little puppy and it's just been
running around for an hour and it's panting and it's got it's tongue lolling out like they do. What's going to happen
when that dog breathes is it's going to breathe
in cool, outside air. Let's say on that day it happened to be 70 degrees Fahrenheit and
it's going to breathe out hot air because the
air that it breathed in is going to equilibrate with its body. If you don't believe me,
put up a hand to your mouth as your breathe out and feel how hot the air is that you're breathing out. What this means is that
the dog is expelling heat everytime it breathes
because it's taking in something cool and
putting out something hot and that heat has to come from somewhere. For dogs this is really important because they can't sweat. They have fur coats and
they couldn't very well soak those fur coats and sweat everytime they want to lose heat. This is really their best
way of getting rid of heat. Now, we humans - and
I'm going to try to draw one of we humans over here
- we humans can sweat. This is a human with an Afro, apparently. We humans can sweat and so this method of losing heat by breathing heavily is definitely less important for us, but it actually still happens. Just like the dog when we breathe in, or when the air that we
breathe in, which technically comes from both the nose and the mouth, that air goes into our
lungs and in our lungs and in our lungs it divides
into all those little alveoli that you've heard about
that have a huge amount of surface area. Let's
me just draw a couple of them here. All these tiny alveoli have a huge amount of surface area and that allows all this
cool air that you breathe in, which I'm drawing here, to equilibrate with the temperature of the blood that's passing by these capillaries. So just like the dog,
when we breathe in air that's let's say 70 degrees Celsius, we're going to breathe out air that's pretty much body temperature. That should not be Celsius,
that should be Fahrenheit. When we breathe an air
that's 70 or maybe cooler, we are going to breathe out
air that's body temperature. If this guy is not having a fever that would be about
98.6 degrees Farenheit. Therefore, we can see that
getting rid of extra heat is another thing that the lungs can do. We have a fancy word for this. We call it Thermo, thermo
meaning heat just like a thermometer measures temperature, Thermoregulation. So you could say it's regulation of the
temperature of our bodies. That's another things
that the lungs can do. Lungs can thermoregulate. You'll note that this
is kind of convenient because times when you
might be overheating, just like this dog,
times when you might be overheating or when you've
done a lot of exercise and when you've done all that exercise you need a lot of oxygen
to feed your muscles and at the same time you
want to get rid of heat. These two functions of providing oxygen and getting rid of excess
heat coincide nicely in the case of exercise
because what happens when you exercise is that you
start breathing really heavily. At rest, you might be breathing
about five liters of air per minute. Meaning that a total of five
liters of air is coming in and out of your lungs every minute, but while you're doing exercise,
let's say heavy exercise, let's say you're running
a mile, trying to get a really good time, you can
easily go up to 50 liters per minute and clearly, that
is a lot more, 10 times more. What that means is you're
going to be putting out 10 times more heat through your lungs than when you're resting.
So it's convenient that when you exercise you get more oxygen by breathing heavily and you also get rid of more heat by breathing heavily.