It sounds like, I don’t know, that that should be the name of a Roman Senator or something. Okay, we’re going to now translate the speech of torus tubarius and, I don’t know, I think someday I’m going to use that as a pseudonym or something, because I just liked the way it sounds. I like the way that comes off of my tongue and sounds in my ear torus tubarius. So what is it? Well, it’s an anatomical structure. It’s not an old Roman senator. I don’t know, maybe there was an old Roman senator by this name. I’m going to look that up and I’ll follow up maybe in the next episode or something if I do find it.

Kevin Patton:
But let’s break that apart into the two words. Torus is the first word, and torus is a donut-like shape. It’s like if you took a long skinny cylinder and then bent it around on itself and joined it into a circle, what you’d have is a donut-like shape. That is what a torus is. It can be fat, like a lot of donuts are, or it can be skinny, but it’s a torus. So that’s the first part. The second part is tubarius, T-U-B-A-R-I-U-S. That, in Latin, means trumpet maker. So we have a donut-like shape that is a trumpet maker. What in the world is that? Well, it makes sense. I mean, the poetic kind of sense that some of these scientific terms have when you look at what it actually describes. What it is, is a structure at the pharyngeal end of the auditory tube, that is the Eustachian tube.

Kevin Patton:
So if you were miniaturized, which is a topic of a later episode that I’m going to do … I often, when I’m teaching Anatomy, I often have my students imagine, do like a little thought experiment and imagine themselves miniaturized and inside the body at a microscopic scale. So let’s imagine that and let’s say we’re in the nasopharynx, and we’re looking at the opening of the auditory tube on a lateral surface of the nasopharynx. So there it is, there’s a little opening of the auditory tube, and what we’re going to see is that there is a circular ridge around it. Now, it may not be complete; that’s going to vary from one individual to another. But it’s going to look almost like we’re looking straight into the bell of a trumpet. The reason is that the cartilaginous part of the auditory tube, which we can’t see because it’s covered over with mucosa, but that cartilaginous part is going to be stiff there at the end. So when the soft mucosa covers it up, it’s going to be covering it up and it’s going to form a little bump over the end of that cartilaginous tube. So that little bump is called the torus tubarius .

Sponsored by AAA

Kevin Patton:
A searchable transcript and a captioned audiogram of this episode are funded by AAA, the American Association for Anatomy. As a member of AAA, I get the weekly Anatomy Now newsletter. In a recent issue, I learned that a small team of physicians in Western Australia, motivated by a Twitter debate on eponyms, has created a searchable database of 700 alternatives to anatomical terms named after dead people. Let’s face it, they are mostly white men. If you go to Anatomy.org and click on News and Journals, you can find the October 7th issue in the newsletter archive and you can read all about the project and find out how to search the de-eponymification database … and, yeah, okay, de-eponymification, I think I’m going to start a project on promoting the use of easily pronounced terms. De-eponymification. Okay, I say it enough times, I’m going to get it down to kind of just roll off my tongue. Anyway, you can find a whole bunch of useful stuff at Anatomy.org.

New Organ

Kevin Patton:
Can you believe it? Yet another previously undiscovered new organ has been discovered in the human body. This time it’s the tubarial salivary gland, which it’s discoverers would like to see it considered to be one of the major salivary organs, along with the parotid, submaxillary, and submandibular pairs rather than as simply another set of the huge number of minor salivary glands that are scattered all around the mouth and throat regions. The name tubarial comes from its location, or I mean their location because it is a paired set. So the location is along the torus tubarius, and, yeah, as I said before, I wasn’t sure what that is either when I first heard it. As I explained in the Word Dissection segment of this episode, a torus is basically a classic donut shape, and that’s kind of the shape formed by the cartilage supporting the opening of the auditory tube into the nasopharynx.

Kevin Patton:
The pharyngeal mucosa then has this rounded bumps surrounding the tubes’ opening, looking like there’s a little doughnut under it. That is what the torus tubarius is. So, yeah, okay, we’re a miniaturized and in the nasopharynx, looking directly at the opening of the auditory tube, and embedded in that tubarial mucosa and extending inferiorly from there are a whole bunch of exocrine glands producing a mucus secretion that’s coming out of a whole bunch of little ducts. The image in the show notes in your podcast app or at the episode page shows this structure clearly, if you can’t imagine it. That image looks almost as if somebody had been miniaturized and took a snapshot with their mobile phone. Mark my word, someday that’s going to be a thing.

Kevin Patton:
Now, I’m always skeptical of discoveries of new major organs, so I’m still kind of taking a wait and see attitude, at least a little bit. Yes, the discoverers did look at many, many individuals and made all kinds of other observations that back up their claim, to a point. But I’m thinking maybe we need a little bit more. I’m not sure. Of course, we need time for science to do its job and let folks replicate and debate and mull over what’s going on. A question I have is that there are multiple ducts observed in the tubarial salivary gland, and I’m not sure, therefore, how it can be distinguished from groupings of the many minor salivary glands we’ve already established in Anatomy.

Kevin Patton:
On the other hand, the sublingual salivary glands have multiple ducts, so I guess the fact that there’s a bunch of ducts doesn’t exactly push the tubarial salivary glands off the list. Any list of what’s an organ and what’s not an organ, or what’s a major organ and what’s not a major organ, and it’s a minor organ is only partly a matter of science theory. It’s also partly a matter of our need to figure out what label we want to put on structures. Those labels are there to help us understand the body better and also to communicate more accurately with each other. So what the community of scientists needs to do now is to figure out whether this newly proposed name and newly proposed designation is a major salivary gland rather than a minor salivary gland is useful or not.

Kevin Patton:
Now, I don’t have a real strong opinion one way or the other about this; just questions. A big question is: Why insist on calling it an organ? In reading the paper, you’ll see that the author’s primary interest in doing so has to do with the clinical implications. If it’s one of the major salivary glands, then it’s worth putting on the list of structures that we want to take steps to spare or protect during radiation therapy, and that’s where these folks are coming from, from the radiation therapy angle. If the tubarial salivary gland is just a random set of tiny glands we imagined to be scattered all over the place, well, then maybe sparing them is impractical. But I think the authors are saying, “Hey, look at these images. These glands are concentrated in a rather defined area. And there are a lot of them, and we can take steps to avoid damaging them now that we know where they are and that they’re even there. And patients will be better off for doing that. So here they are, and here what we’re calling them because they need a name to put on our list of things to consider when planning radiotherapy for a patient.”

Kevin Patton:
So when you look at it from that angle, maybe calling this structure an organ is not such a bad idea, I don’t know. As usual, some folks are calling for a rewriting of textbooks. Well, I always want to hold on a minute when I hear that cause you I hear that a lot. Maybe I’m just … my ears are sensitized to that. What? Something needs to go into a textbook? A lot of times, it’s something that’s just way too early to go into a textbook, something that’s going to be soon disproven or at least modified in some way. The other thing is, is that, especially for undergraduate A&P textbooks, we have to ask the question, “Is this really a detail that our students really need to know?” Even at an advanced level, like in a medical anatomy course, there are some things that maybe are just too much and maybe don’t have a clinical or practical application. I think this one does, but I’m just saying, in general, those are some questions that have to be asked before it actually gets into textbooks. Things don’t just automatically flow from journals into a textbook. There’s all kinds of editorial decisions to be made, and scientific questions and decisions and observations need to be made.

Kevin Patton:
So are we really ready for that at this moment? I don’t know. Maybe science has to do its work a little bit more so that we have greater confidence in that idea. Or, maybe it is time now. Why don’t you call in to the podcast timeline and tell me what you think. But no matter what, I’m also thinking it’s a great time to mention it to our students. Even if it’s outside the official content of our course, that is, maybe even if we’re not going to put it on the test, make it into a test item, maybe we want to discuss how science works and this is a good opportunity to do that, and it’s also a good opportunity that we don’t already know everything. It’s a good opportunity to discuss what makes an organ an organ, which is a lot fuzzier than a lot of students imagined. Well, there’s all kinds of interesting things that can come out of such a discussion, right? By the way, we have been discussing this in The A&P Professor community. You can join that conversation at theAPprofessor.org/community.

Sponsored by HAPI

Kevin Patton:
The free distribution of this podcast is sponsored by the Master of Science in Human Anatomy and Physiology Instruction, the HAPI degree. It’s for folks who already have an advanced degree, but want to fill in the gaps by reviewing all the concepts of A&P and also the contemporary theory and practice of teaching. I’m on the faculty of this program and I regularly hear from our graduates about how what they gained from the HAPI experience is helping them every day in their teaching, and often helping their colleagues, too, when they share what they’ve learned from the HAPI program. Check out this online graduate program at nycc.edu/hapi, that’s H-A-P-I, or click the link in the show notes or episode page.

Secret Language of A&P

Kevin Patton:
If you’ve been listening to this podcast for a while, especially in the early episodes of this podcast, so that was a long time ago, you know that I like to play games with my students in class. What I mean by that is not necessarily classic games, and I do know that a lot of A&P teachers really get a lot of benefit out of using all various sorts of board games and modifications of Jeopardy and other game shows and things like that to teach Anatomy and/or Physiology. Those are all great, but that’s not what I mean by this. What I mean is I just play around with them and do different things.

Kevin Patton:
For example, in the previous episode, when I was talking about the Krebs cycle … and I left a little gap there on purpose because if you did listen to Episode Number 79, you know that a game I play with my students is to tell them that every time they hear the term Krebs cycle, that they should respond with an emotional, “No, not the Krebs cycle,” because then that’s going to make everybody think that they really had a lot of in-depth experience with the Krebs cycle, because in my class I don’t go into it that deeply. I talk about the important parts of it, the parts that students really need to know in order to understand metabolism and can really make practical use of in various other contexts where this idea of metabolism comes up, without having to go into every single step of that whole process. So it’s a game that we play. It becomes fun. We laugh out loud sometimes when people over-dramatize their response to that, and so on. So it’s not part of the content. It’s a playful thing I do.

Kevin Patton:
Another one of those little playful things I do as I talk, and I start this at the very beginning of the course, I talk about our secret language. I’m kind of violating the rules here by putting this out in a podcast where anyone in the world can hear about it, because that sort of violates the internal rules of the game. Because I tell my students that part of what they’re doing in my course is learning a secret language of a secret society. I tell them that they never heard of this secret society before, because, after all, we are a secret society and we’ve done a good job of keeping it secret. So, yeah, okay, it’s a secret society that you’ve never heard of because it is a secret society and we have a secret language.

Kevin Patton:
What you’re going to be doing in this course is getting your first several degrees or levels of secret knowledge, because, you know, secret societies, that’s kind of what they’re all about, right, is to initiate their members into secret knowledge that the majority of the population doesn’t really knowledge. Now, when people go to study these secret societies and they find out what the secrets are, you find out that it is stuff that everybody else knows, or, at least, many other people know. It’s kind of the way with our secret society, but it’s a game, right? So I tell them that I’m going to be teaching them slowly but surely about these mysterious sounding things like torus tubarius and they’re like, “What? What is that? I never heard of that.” Yes, that’s right, because it’s part of our secret language.

Kevin Patton:
Even if you heard it, you wouldn’t know what it means, but I’m going to teach you what it means. Even things like de-eponymification … Wow, that came out the first time and I didn’t even edit that. I swear I did not edit that, de-eponymification. Wow, I’m mastering that term and I tell them that that’s what it’s all about. It’s about mastering these terms 1 or 2 or 10 at a time, just like you do when you learn any other language. You’re going to find out that like the knowledge in secret societies, all these things have simple meanings. They’re not that complicated, they just sound complicated. But that’s what we do in a secret society, that’s why we have secret languages, is so that other people don’t know what we’re talking about, right? So, yeah, okay, you can take it or leave it. Maybe that’s not something that fits in the persona that you want to project in your class, but I project a kind of goofy persona so it fits right in with what I do. Maybe there’s some way you can adapt that, or maybe this sparks some idea for how you can handle the language of science, the language of Anatomy and Physiology, and maybe a more playful way than you normally do.

Sponsored by HAPS

Kevin Patton:
Marketing support for this podcast is provided by HAPS, the Human Anatomy and Physiology Society, promoting excellence in the teaching of Human Anatomy and Physiology for over 30 years. In the previous episode, I mentioned the virtual regional conference coming up on November 7th. They have a pretty good program planned, I’d say a great program, and I’m all signed up and I’m looking to participating. I hope I’ll see you there. For information or to register, just go visit HAPS at theAPprofessor.org/haps, that’s H-A-P-S.

Dam Protons

Kevin Patton:
Right now, I want to talk about those dam protons. When I say dam protons, I mean, protons behind a dam. This all fits in with that whole playful idea I was talking about in a previous segment, which fits in with what I was talking about in the last episode where I was telling the story of the Krebs cycle. Yes, the Krebs cycle, the horror of it. I said that I kind of do this playful little analogy where I think about the Krebs cycle … I’m leaving a gap there. Now, I hope you’re practicing this. If you’re not responding out loud, you’re just not playing along with the game. Now, come on, join in. You can do that even if you’re by yourself. You can do that. Okay, at least, do it in your head. All right, so I’m going to be leaving those gaps for you, just like I do with my students.

Kevin Patton:
But the story I tell, which I didn’t really tell in the last episode, at least not completely, I was telling was sort of a meta story. I was telling you the story about how I tell the story, not telling the actual story itself, which is pretty long and convoluted and traumatized and so on. So I hope it made some sense, but basically, in a nutshell, to recap what happened in the last episode or would have happened if I really explained everything, is that we start out with a glucose molecule, at least, the initial telling of the story. Now, later on, we can go back to that story and go backwards a little bit and talk about glycogen and things like that.

Kevin Patton:
But we start with a glucose molecule, a six carbon molecule, and we go through some steps in glycolysis to break that down, and we’re going to end up with a three carbon molecule pyruvate. That is what’s going to go into the Krebs cycle.

Speaker 3:
Oh, no.

Kevin Patton:
Or we’re going to try and get it into the Krebs cycle.

Speaker 4:
Oh, no.

Kevin Patton:
And yes, that’s horrible because it’s sort of like this giant Ferris wheel from a Stephen King novel where we can see that these molecules are getting on, the car at the bottom there, they get on and we watch that car go up and around just like we would watch somebody on a Ferris wheel, and we see that carbon-containing molecule is being broken apart and there are pieces flying off as CO2s and this high energy electrons with their protons floating along with them, chasing after them, and like, “Oh my gosh,” it’s like watching somebody getting onto a Ferris wheel and seeing body parts flying off. Then they come back around and that car is empty. Whoa, that is scary. If I were a molecule and saw that happening, well, I probably wouldn’t be conscious, at least not in the way where I could watch that thing. But yeah, okay, that’s crazy. That’s adding a little depth to a story that could otherwise bore students who are not innately fascinated by biochemistry like you and I are.

Kevin Patton:
So the pyruvate, we break off another carbon and we get a acetyl, and acetyl gets grabbed by coenzyme A, which pushes the acetyl kicking and screaming into the Krebs cycle.

Speaker 5:
Oh, no.

Kevin Patton:
Or otherwise known as the citric acid cycle. So then some more breaking happens in that cycle. I had already told them that the energy that’s being released by this process, and that’s why we’re doing the process is to release energy so we can eventually get it into ATP and it can actually do us some good in various parts of the cell. I tell them that it comes off of these molecules as high energy electrons with their protons floating along. So that’s where I left the story in the last episode, Episode 79.

Kevin Patton:
But in this episode, I want to pick up and go into the sequel to that because we know there’s more to the bigger story, right? We know that those high energy electrons are going to be grabbed it by some more coenzymes because that’s what coenzymes are, they are grabbers, at least that’s one of their jobs. Just like they grabbed the acetyl and pulled it kicking and screaming into the Krebs cycle … no, no, not the Krebs cycle … we have other coenzymes like NAD and FAD that are going to be picking up the high energy electrons and/or protons and catching them, and shuttling them over to the electron transfer port system, which is built into the mitochondria. So we reviewed that whole structure of the mitochondrion and the fact that there are these pathways, there are these enzymes that are there that can do some more processing.

Kevin Patton:
So the electrons as they travel along that set of enzymes, their protons are going to be pushed into that space between the air membrane where the electron transport system is and the outer membrane. When we look at the concentration of protons on the very inside, inside the inner membrane, we’re going to see that it’s very low. But when we look at the concentration of protons in between the two membranes, between the inner and outer membrane, we’re going to see that it’s very high. So, in a way, it’s like water behind a dam. Now, like any analogy, that falls down on several points, but one of which is that water behind a dam is a pressure gradient. It’s actually caused by a natural force called gravity. It’s gravity pulling on the water, pulling the water against the dam.

Kevin Patton:
Here, we have a different force of nature that has to do with concentration gradients, but it’s still a force of nature and it’s still pulling on those protons, or, at least, we can think of it that way, and the protons really want to get across to the other side. Just like with a dam, if we poke a hole in the dam, the water’s going to come rushing through. Or, if we cut a groove in the dam, the water’s going to come rushing through. The same thing is going to happen to those protons. If we provide some kind of a channel for the water to get through, or, excuse me, for the protons to get through, they’re going to go through. Why? Because there’s a force of nature that’s drawing them that way. Sure enough, we do that.

Kevin Patton:
Now, when you have water behind a dam, what you can do is you can make a little channel and have that channel directed at a water wheel. As that water comes over the dam and through that channel and that water spills onto the water wheel, it’s going to cause the water wheel to turn with force. So the force of that water moving, it’s going to be converted into mechanical force that can be used to mill a grain or produce electricity if it’s causing magnets to spin around inside a coil, or a number of other kinds of things that we can do, and make use of it and grab a hold of that energy that was basically being stored as potential energy behind that dam.

Kevin Patton:
So those protons behind that membrane are potential energy, and we can trap, at least some of it, by letting it go through a channel like a water wheel. That’s where our ATP synthase comes in. That is a molecule that’s very much like the turbine in a hydroelectric dam or like the old style water wheels that were used on various grinding mills and so on. So as the protons come from the high concentration area, through the ATP synthase in the inner membrane, so that it can go into that inner space of the mitochondrion, the inner chamber there, then those protons can cause the ATP synthase to spin around like a water wheel. The energy of that can then be converted in such a way that it can phosphorylate ADP to become ATP. So we can add phosphate groups to ADP. We know that that’s a way to temporarily store energy. You can’t store it for very long. We’ve got to go use it right away somewhere.

Kevin Patton:
But what we’ve done at that point is finally gotten the energy out of that glucose molecule and into a form that we can actually use in other parts of the cell. Yippee, that’s important, but we need to go back and say, “Well, where does that leave the main characters in our story?” We had the high energy electrons bouncing from one enzyme to another in the electron transport system, and while there that was going on, we had a little side story, a little subplot going on over here, what was happening with the protons, where they were getting pumped to that outer area and now they are being allowed to flow back down into the inner area, and they can meet back up with their now not such high energy. They’re low energy electrons or lower energy electrons that are now pooped out and they meet one another. They come together and the high energy electron is saying, “Oh, you wouldn’t believe what happened. I got on this crazy Ferris wheel and got … Oh man, it was this crazy and horrible and I was scared.” The protons said, “Yeah, I lost sight of you there for a minute and I got pumped behind a dam and then I went through this hole in the dam and spun around, and that was crazy.”

Kevin Patton:
So they’re just glad to be back together, but the problem is we can’t have all these pair of electrons and that pair of protons. They get together, they would otherwise form H2, which is hydrogen gas, and that could cause all kinds of problems. It could cause other problems even if it doesn’t get together so, yeah, biochemically speaking, we need to do something with this. That’s where oxygen comes in, is that final acceptor of electrons, right? It’s actually the electrons and the protons that are being accepted and we form H2O, so that’s why water becomes the by-product of this whole catabolic pathway and it’s also why we need oxygen. We need oxygen at the end of there to catch those now used up and depleted, energy-depleted, pairs of electrons and their protons.

Kevin Patton:
So, okay, again, I go into more detail and explain things a little bit more clearly to my students, but I was kind of rushing through it there, because I don’t want you to have to listen to a super long podcast episode. Anyway, you tell your own story, if you even want to tell a story. But this gives you an idea of the kinds of stories that I tell in my class, in case that sparks some idea for you. Or, maybe it’s just another one of those things where like, “Man, that Kevin, he is one weird dude,” and it’s just part of that story.

Staying Connected

Kevin Patton:
Hey, hey, hey, don’t forget that I always put links in the show notes and at the episode page at theAPprofessor.org/80, in case you want to further explore any ideas mentioned in this podcast or if you want to visit our sponsors. When you do interact with our sponsors, I’d really appreciate it if you mentioned the fact that you hear about them on this podcast on a regular basis. That’ll help everybody. You’re always encouraged to call in with your questions, comments, and ideas at the podcast hotline. That’s 1-833-LION-DEN, or 1-833-546-6336, or send a recording or written message to podcast@theAPprofessor.org.

Kevin Patton:
We’d love to have you in our private online community, well away from the ads, the spam, the tracking, the algorithms that hide what and who you want to see; the convoluted email threads and the bullying. As far as I know, no foreign governments or bots have infiltrated our group either. It’s a comfortable, supportive space filled only with A&P faculty like you. Just go to theAPprofessor.org/community, and join one of our live check-ins every Tuesday afternoon. That’s theAPprofessor.org/community. I’ll see you down the road.

Aileen:
The A&P Professor is hosted by Dr. Kevin Patton, an award-winning professor and textbook author in Human Anatomy and Physiology.

Kevin Patton:
This is a relatively safe podcast, but actual crash results may vary.