First-Line Defenses: Chemical Barriers

in this video, we're going to continue to talk about the first line defenses of innate immunity by focusing specifically on the chemical barriers. And so once again certain types of chemical factors play important roles in the first line defense mechanisms of innate immunity. And so here we have just a little bit of a warning that if our lesson hasn't already, it may get a little bit gross in this part of the lesson because we're going to talk about things like sweat and earwax and saliva and stuff like that. And so here notice we're showing you our map of the lesson on innate immunity. And already we've talked about the physical barriers of the first line of defense. So now we're moving on to the chemical barriers in the first line of defense. And so notice that c bum, sweat, earwax, saliva, gastric juices and a mps are all part of the chemical barriers of the first line of defense of innate immunity. And so moving forward in our course, we're gonna talk more about each of these different types of chemical defenses that you see here in this lesson. And so uh I'll see you all in our next video

in this video, we're going to talk more about the chemical defenses of the first line of defense of innate immunity by focusing specifically on Sebum and how sivam helps to prevent microbial growth as a protective layer on our skin. And so sebaceous glands are specific glands on our skin that produce an oily substance called sebum. And so see them. This oily substance serves as a chemical barrier that can prevent hair from becoming stiff and brittle. But it also can contain fatty acids that can help lower the ph of the skin. And the lowering of the ph of the skin can thereby help to prevent growth of certain types of microbes, thereby protecting us from certain types of microbes. And so if we take a look at our image down below notice we're showing you our little map over here with the first line of defense is specifically the chemical barriers and we're focusing in on see them right now at the moment. And so we're showing you here the sebaceous glands that are present and the skin here. And uh we can label this as the sebaceous uh sebaceous gland and the sebaceous gland is able to secrete oil. Uh so that the oil that serum which contains oil is going to be on the surface of our skin. And again, that can help to protect us from certain types of microbes. Here's another image that's showing you how a micro graph of the sebaceous glands can look like. And so this here concludes our brief brief introduction to see them as a chemical defense mechanism. And we'll be able to talk about other chemical defense mechanisms as we move forward in our course. And so I'll see you all in our next video.

in this video, we're going to continue to talk about chemical defenses by briefly focusing on sweat and sweat glands prevent microbial growth by perspiration and perspiration is the process of sweating or in other words, the process of releasing sweat from the sweat glands on the skin and this release of sweat helps to lower the body temperature. And it can also help to remove microbes from the surface of our skin. Also, sweat contains many different types of chemicals, including an enzyme that we refer to as listeners. I'm and so license I'm is an enzyme that degrades bacterial cell walls and therefore it can help to protect us from pathogenic microorganisms that are trying to invade our bodies. Now listen, as I'm uh this enzyme listen is also found in tears, saliva, urine mucus and tissue fluids. And so this chemical listens I'm can really be beneficial to help protect several different areas and regions of our body. And so if we take a look at our image down below at our map notice we're focusing in on the first line of defense, specifically the chemical barriers and this time we're focusing specifically on sweat. And so here in this image, we're showing you an image of the sweat glands and so notice that the sweat glands in this image are over here and over here and once again, they are able to release sweat onto the surface of our skin, which can help protect us in many different ways from invading microbes. And so this here concludes our brief lesson on sweat as a chemical defense mechanism and Lissa sign as a chemical defense mechanism. And so we'll be able to learn more about other chemical defenses as we move forward in our course. And so I'll see you all in our next video.

in this video we're going to briefly talk about earwax as a chemical defense. And so earwax can help prevent microbial growth by controlling the P. H. And so erects can actually serve as both a physical and a chemical barrier in the first line defenses of innate immunity. And so it can physically prevent microbe entry into the ear. And uh earwax can also control once again the P. H. Of the environment. And so earwax which is a complex mixture that contains C. Bomb which is rich in fatty acids. That can actually help to lower the P. H. And the lowering of the pH can help to inhibit microbial growth. Also, earwax also contains many skin cells and these skin cells from the ear canal contain keratin and keratin Once again is going to help create a dry environment that can also help to protect our bodies as well. And so if we take a look at our image down below, over here on the left hand side notice we're showing you our first line defense map, focusing in on the chemical barriers and focusing in on earwax here in this image. And so over here on the right, once again we're focusing on earwax as a chemical defense as well as a physical barrier as well. And so notice here that we're showing you an image of the ear and the ear canal here and you can see that there's earwax within the ear canal. And of course this earwax is going to contain chemicals antimicrobial chemicals that help protect us from microbes and it can also help to lower the ph to inhibit microbial growth. And it can also physically block microbes from entering as well. So notice this image over here is portraying that you can see these microbes that are trying to enter through our ear canals are getting stuck in the ear wax into that serves as a physical barrier as well. And so this year concludes our brief lesson on earwax as a chemical defense as well as a physical barrier. And we'll get to talk more about other chemical defenses as we move forward in our course. And so I'll see you all in our next video.

In this video, we're going to briefly talk about saliva as a chemical defense that can prevent microbial growth. And so saliva is a complex mixture that contains enzymes that can actually inhibit microbial growth. For example, the enzyme listeners, I'm so recall from our previous lesson videos that the enzyme listeners I'm mhm uh is an enzyme that is going to degrade the peptidoglycan layer of bacterial cell walls, thereby preventing microbes, those bacteria from growing. And so if we take a look at our image down below, over here, on the left hand side, once again, we're showing you our map of the first line defenses, focusing in on the chemical defenses here and focusing in on saliva. And so saliva once again, which can be found in our mouths, is going to contain some enzymes and those enzymes can inhibit microbial growth. And so notice zooming into this little cartoon that we have here notice that these microbes here are not able to grow in the conditions with the saliva. And so our saliva contains enzymes that limits microbial growth and prevent many microbes from being able to fully settle and uh causes harm. And so this year concludes our brief lesson on saliva as a chemical defense mechanism. And we'll be able to talk about other chemical defenses as we move forward in our course. And so I'll see you all in our next video

in this video, we're going to briefly talk about gastric juice as a chemical defense that can help prevent microbial growth by lowering the ph. And so gastric juice uh is really just going to be a complex mixture of many different substances that includes hydrochloric acid or hcl as well as several different types of enzymes. For example, license I'm and mucus all in the stomach. And so this highly acidic solution is going to lower the ph of the stomach, which is therefore going to kill most of the bacteria that are ingested. And it will also inactivate most toxins as well. And so it does serve as a first line defense, a chemical means of protecting us. And so if we take a look at this image down below on the left hand side notice we're showing you a map of the first line of defense, specifically the chemical barriers. And we're focusing in on the gastric juices here. And so gastric juice again is going to be a complex mixture found in our stomachs, as you can see here. And so we can label this gastric juice. And what you'll notice is that the ph is going to be very, very acidic. And so notice here, it says the ph is about 2.5. And so notice through this little cartoon here that these microbes are most microbes are not capable of surviving in these acidic conditions. And so it is so acidic here and notice this one saying is uh it burns. And so it's just showing you here that many microbes are not capable of surviving those acidic environments within uh, the gastric juice within our stomach. And so this year concludes our brief lesson on gas, your juice as a chemical defense mechanism. And we'll be able to apply some of these concepts that we've learned as we move forward in our course, and then we'll get to talk a little bit more about some other chemical defenses. So I'll see you all in our next video.

in this video, we're going to continue to talk about chemical barriers that serve as first line defenses of innate immunity by focusing specifically on anti microbial peptides. And so anti microbial peptides are commonly abbreviated as a mps. And as their name implies, anti microbial peptides or a mps are going to be short chains of amino acids with anti microbial activity. Now these mps can be found in many organism types and they are generally made in response to an invading microbe and there are many different types of mps that include defenses, bacteria sends Catholics, sittin down, Poseidon and his students. But here in this video we're only going to focus briefly on defendants. And so defenses are a type of a Mp and they are positively charged A mps that actually damage microbial membranes by inserting into the microbial membranes and causing those microbial membranes to lice. And so it causes like ISIS. Now these defenses can be produced by our own epithelial cells, epithelial skin cells to help protect our skin and to help protect our mucous membranes in order to prevent an infection. And so if we take a look at our image down below, over here on the left hand side, notice that we're showing you the map of our lesson on the first line defenses here, specifically focusing focusing in on the chemical barriers and talking about the A. M. P. S here in this video. And so these anti microbial peptides, which again can be abbreviated as a mps are going to be these short little peptide chains. Short little amino acid chains with anti microbial activity. And so we can label these as the antimicrobial peptides and notice that these anti microbial peptides can be released by our epithelial cells, and they can affect these microbes here and affect the membranes of those microbes and cause cell like ISIS. And so this year concludes our brief lesson on anti microbial peptides as a chemical barrier, uh protecting us as a first line defense in an immunity. And so we'll be able to get some practice applying these concepts as we move forward. So I'll see you all in our next video.