Inspiration and Expiration

labeled for reuse on flickr

Yes. Indeed this is another post about science. Human anatomy to be specific. If you don't find it interesting, well there's an easy solution. I'm sure you can work it out. In any case, if you don't want to read this, I hope to see you soon!

Now on to those who need to know this for school, or this is a controversial idea, actually find this interesting, I will try to explain inspiration and expiration. 

Hint: Itty-bitty blood vessel makes another appearance. Again, if you haven't read my past article about this, let me reiterate that I actually mean capillary. Please don't call capillaries, itty-bitty blood vessels on anything of importance.

Moving on. So inspiration and expiration are absolutely vital (and I don't mean this in the hyperbolic way that this word is often used), without these two processes, you would be dead. Literally. Not figuratively. Literally. Why? Well these are the two mechanisms involved in breathing. You know the thing you do so you get oxygen? Kind of important when you think about it. Another use? Well during cellular respiration (I will cover this later) we produce CO2 (sorry I don't have a subscript key). You should know carbon dioxide is kinda toxic to your body. So it's a tad necessary to get rid of it. This is also accomplished by our friend expiration. I just noticed how similar the word friend and fiend are. I better remember my r's... 

I'm sure you are all dying to know how it works at this point. *crickets* 

Anyway. There are five (I believe) mechanisms that are involved in inspiration. Yes, there are also five in expiration, but patience young grasshopper. Hold your horses, etc. etc. 

Numero uno. Your external intercostal muscles (located near the ribs) contract, stretching out, thus pushing out your rib cage. At the same time your diaphragm contracts. This means that it extends downwards. Finally one set of abdominal muscles also contract.

So what does all this contracting accomplish? No. It does not accomplish overpopulation. Goodness. It means the volume in your lungs has increased. And what do we know about the relationship between volume and pressure? 

Come on people. Say it all together. They are inverse to each other. So as the volume in the thoracic cavity increases the pressure decreases. Good. I'm glad we've gotten this sorted. 

And since pressure has decreased, well, surprise surprise, so has the pressure on the lung tissue. Gasp. Yes I know. It's true. Radical. 

What happens next you ask in fascination? Well. I'll tell you. Maybe. Yes. Okay. Well, a partial vacuum is created. No not the thing you clean your floor with, trust me I've had a 20 minute conversation with someone about vacuums, all the while they thought I was talking about the household appliance, when in reality I was talking about black holes... Anywho, partial vacuum created.

Now, with this partial vacuum created, air from the outside world with flood in through your nasal passages, and/or mouth. Because, well gases moves from areas of high pressure to low pressure. And as I hope I've made clear, there is a lower pressure in the lungs. 

Pfew. We're done. I think I neglected numbers after número uno. Well, I'm hoping you can figure it out... More to come soon.