Biology 1al - Lecture 8 - Lab 8 - Invertebrates i

>>INSTRUCTOR: Okay, good evening a few comments about biology 1A, although I know this is 1 AL I've been getting lots of e mails because you're getting lectures and two back and discussion today or tomorrow if you go to discussion, so I'm getting lots of e mails saying, you know, I want to be, what do I have to do? So I try to address that in the e mail in the lab class, so the bottom line is if you want a B, in the 1A class, you need to look at the answer keys, for exam 1,and you'll see that the B range for exam 1 is solid B is 87 to 84 points. And for exam 2, solid B is 87 to 84. So, if you want that, you should have been at approximately, let's say 85 to give you a little wiggle room on exam 1, and 85 on exam 2. And the only thing that will change is what this range is depending on by what grade you want, if it's an A, A , etc., and then you need to see how you did on exam 1, so if your score on exam 1 is a 60, you need to make up 25 points. If you score on exam 2 was a 67 you need to make up 18 points. So, then on the final, you need to do B work and I have no idea what that will correspond to in terms of percentages we do guarantee 80 to 89% is some form of a B that's a guarantee we will keep that, but we may curve it down, I don't know, bottom line is you need to get a B on the final, plus make up those 43 points. The finals worth 300 points, so it's worth a lot more than any given lecture exam. Also, keep in mind at the end of the semester, we will take into account your iClicker points, and your mastery biology. And for master in biology I started to figure out the scores for that, basically what happens is, you know for part 1, I don't remember the number, but let's say it was 243, there are 243 possible points, now you'll get [Indiscernible] what we said was the maximum would be 24 points, that's the max. But we had weighted this to 26 points, so what I would do is take your score in part 1, and I multiply it 46 by 43, if it's over 24 you get 24. If this 24 is the maximum this allows you potentially miss a homework assignment and still get the maximum possible score, if it's under 24, and then you get those number of points, I've done the same thing for part 2. The slight problem I run into, I started to do this, try to match up the ID's that students try to register with, and then we have about 100 students that have exact same Cal ID which is M Pauly 69, Berkeley, I don't know, but apparently not with a Cal student ID, but with that. Now I can try to match up names but the problem is people didn't use they're real name so I have no idea who Joe blow is but they're not the class but they're a student. So once I figure that out I will post on bSpace what you're master in biology is, if you can figure out that I will take and tell you what the maximum is worth part is or part 2 you can go online and see what your scores are. Does this make sense? And with the iClicker there's no idea there are students who haven't registered clickers so I have about 75 clickers that have been clicking with no one registered to them. So I'll post another e mail to say last time to register your iClicker and register for files. So you can figure out how you're doing in the 1A class by looking at the cut offs you can figure out how you need to do. If you can determine you need to make up 125 points ton final that's not realistic. Because that would be like a 360, probably. It's worth only 300 so you to be realistic in your assessment on that. So, any questions a about that? No, okay to like with 1A the lab class, I seen on a spreadsheet I highlighted what I thought was doable in terms of making up points in green, people asked me what about the numbers down below there, I don't think they're really possible, so in other words, on lab exam 2 you need to make up 35 points realize it's worth only 64 points you're not going to get a B and make up 35 points it's impossible, it exceeds the maximum possible number so that's why I didn't indicate the other point values, any questions about that? So what we're going to be doing here is we're going to talk about the Poriferas and sponges, there's a third one we're looking at, I keep getting asked how can I study, what's a good way, I've tried to go over this before I want you to know unfortunately I do not have magic hands I can't put on you say you will get an A I wish I could, okay. But I don't. So instead what I can do is only give general advice so for the 1A class, it's extremely helpful to make drawings for the various lectures, so for example, today, in terms of Dr.ﾊWise blot's lecture, one piece of paper, all of the notes on one piece of paper, like wise the next lecture, next lecture so when you go to study for the final for him, you maybe 12 pieces of paper. If you go back and do the same thing for Dr.ﾊFischer and Dr.ﾊPauly, then when you study there's 36 sheets, ideally you'll take 1 pages from one professor and merge them into one, the it allows you see the intersection connections, the wise blot because with mean of [Indiscernible] those types require to [Indiscernible] the material more, it will be help to take the 12 pages of paper and try to integrate to see the interconnections between the different organ systems. For the lab class, fill out the sheaths charts, you should make a tee and just say, by lateral symmetry or how many have 3 germ layers, write all of them. Various ways to think about it. Okay. So we're going to do phyla today, let's run through some of this. Resources. There's old webcasts you watch. The lab exam is Wednesday 28th, everyone will take the same exam so I will not adjust lab exam 2, because it's a standard exam taken by everyone, the only scores that get adjusted are the quizzes and probably no more than 8 points from the bottom of the 26 sections along that line the scores fall upon the line. All right. So anyway, I'll show you how the exam worked in the past. I can't show you how it works this semester but I can describe it because we've not every used this format in this past it worked like this there would be a station set up, 3 stations set up. Students will be given note cards with given numbers, so they go to the station. Student go to station 2, they have timers, they have 1.45 to read the questions and answer the questions and when the buzzer went off they had to move to station 3, which was to the left, the person who was at 3 went to 4, so they did that for a minute 45 seconds. In other words, maybe if you start at station 3, you would have had, you know, if you started at 2 you had advantage for 3, potentially well you didn't you started at 3, so second rotation, but this is basically how it works you can see we have a sheet plug in there, heart model, and various questions. And this just gives you a close up of this, so the way this is going to work now, for the exam, is I'm going to have a bunch of questions. It's one exam that we printed out. Will consist of color imagines and probably black and white pages as well, various questions, fill in the blank, maybe some multiple choice probably, but a lot of will be fill in the blank where you have to just like in lab exam 1 in the past but you don't have to rotate so you can spend as much time as you want on question 423 you finish in 0 seconds you can move to question 5. It will be color, it will require to have some very good photographs we're doing the best we can in terms of those photographs and it will take about 80 to 100 hours of the photographs, Photoshop them have clear labels. We'll probably do this something like this here where you see an image like this and we'll have a pointer and ask you about what's at that pointer and/or realize we can ask analogous questions as well, we may have the pointer ton structure there, which is called the typhlosole, we ask what the function is, we know what analogous structure in a human, or rat, various things like that, so make sure you think about analogous structure, that is those structures that have the same function. And basically, we'll have some tables. Where you have to fill in tables and they will be listed the various organisms beyond have to fill them in. Gas exchange, so realize that if we the pointer on the skin here I have to target your answer because you can say what's the function of that? If I say just what's the function you say protection, you say prevents desiccation, so I want you to focus on the gas exchange but I have to write the question that you know it's for gas exchange and then you would have to put lungs on the rat or alveoli, something like that. So that will be the format of that. You look at the rat now, so you're familiar with these organ systems so you ought to be able to name various parts within a given organ system but it's excretory, or immune, things like that. In terms of keeping track of all of this information I get repeated e mails and e mails how do I keep track of all of the information it helps to organize it. You can write the number of specie, etc., but some sort of diagram like this is helpful if you take it yourself and are able to make it yourself, that will be useful. Now in the past in lab exam 2, people really struggled with this part with the time rotation because it took awhile, often sometimes the students would write the Cladogram to answer one small question it would take too long. Maybe you won't need to have 10 minutes to redraw the Cladogram to answer 2 or 3 questions, I don't know I'll try to time it so you get through it efficiently well in the allotted time. But have the Cladogram at the snap of your fingers you can quickly figure it out. And often sometimes we ask you to work backwards so the question might be what's the smallest clade that includes these three groups. Okay. If I had a cockroach and then a snail and asked what's the smallest group in that case it could be protostoma. So you need to be able to work backwards I'm never going to ask you what's the largest groups you can say eukaryote. There's this tree here that you can look at, this is another way of adding it. Aye add names of classes here that you need toe no. Yes you certainly need to know every one of these for sure. Okay. Now that doesn't mean I'm going to ask you a question about each and every one, but there's going to be a subset of these, you won't know, I won't know until I write it. We talked about the hierarchy, cells given rights to tissues... (Reading). Epithelia to make a surface. We talked about epithelial, nervous, muscle and the other unusual one, with the cellular matrix, which is connective tissue. We talked briefly last time about rate is proportional to some constraints do you have to that substance in particular but it's proportional to the cross sectional area where the diffusion is occurring the length that it has to diffuse a cross and the concentration gradient so if I'm trying to diffuse in this direction, I have some substance X, it has some rate K, that's going to be proportional to the cross sectional area which it can diffuse a cross, and then it concentration gradient, if I can make more of a gradient, the rate should be faster. And if I can decrease the distance, the rate will be faster. Okay. So we see things in particular that really do a lot of to increase the surface area, microvilli, things like that. So you have that cross sectional area, you have the length or the distance and this... This can be changed sometimes but not greatly. It's usually in terms of design organism cross sectional area, and that's known as fix law. If you have a single cell such as the pro us the that we looked a in the the first lab there they're small enough the gas can be across the service and capturing nutrients through phagocytosis, so it would be intracellular if we get to organism like this like the Cnidarians that have two cell areas the epidermis and the endodermis, now I didn't say endoderm, endodermis, endoderm is a germ layer during development. So I don't know if you remember Dr.ﾊFischer was talking about the ectoderm of the liver he went epithelial cells. So in this case, the dermis the outer layer could be ectodermis, so sometimes it's called gastrodermis. Now they I have a gastrovascular cavity it's no at coelom, that means there's on opening, the mouth slash *** that leads to the cavities like we have a mouth that leads to our oral cavity, a lot of times people think of the mouth as being, you know, part of your body because when you close your mouth it's no longer open to the outside so you can control that, so technically speaking this is open to the outside but only when the mouth is open or the mouth/*** so this is called the gastrodermis and ectodermis or epidermis, now this is thin enough we can still have diffusion across there we don't need to have a special system for fluid with gases dissolved we talked about our body's a tube, the GI tract within another tube, the outside body wall and we invagination to increase surface area, we talked about this coelom before, saw the rat before you cut into it you can see the abdominal cavity, separated by the diaphragm that was a coelom you that had GI tract and the space in there, allow the GI system to keep a peristalsis and the outer body wall didn't ripple. So peristalsis there you can see that it occurs in the rat for several hours, but a true coelom means you that GI tract and it is surrounded by mesoderm called peritoneum, tissue connections, etc., etc. Pseudocoelomates they do have that cavity, all right. But, its not surrounding mesoderm doesn't surround the GI tract you can't get epithelial cells it to. These are acoelomates but they're still protostomes. I want to clarify it because it's always confusing to people. [Indiscernible] that group is put in the protostomes in and particular it's put with the Lophotrochozoans. And that's the [Indiscernible] Platyhelminthes. The ancestral forms had a coelom. And we will talk about how that coelom was formed. It just so happens during evolution this group has last it so when we look at the living members they no longer have a coelom it's solid packing. Okay. So they still we can talk about them being the protostomes and that's the tough about this when we look at organisms it's hard to figure out what happened in the past. Yes, question? >>STUDENT: [Indiscernible] >>INSTRUCTOR: This is justﾊ this is the term coelom. Pathelminths. I didn't finish the rest of it. Yes. Yep. And we'll talk about those shortly, okay. Any other questions? All right. So, just in terms of the GI tract verses a cavity, and [Indiscernible] with have a cavity, one opening the flat worms will have one opening, the exception to this are the tapeworms are cestoda where they don't have a GI track they don't have a digestive system and the reason they have lost they're digestive system evolutionary is they're in the nutrient rich environment of their host so they absorb nutrients from they're host just from the skin. So they don't have a digestive system in the tapeworms.ﾊyou can see the two layers here, the epidermis, or endoderm there is a thin layer of the and no the jellyfish you can see it's thick. We'll talk about mating. This is illustration of the earthworms, *** reproductions these are hermaphrodites, this organism has both testees and ovaries so it's hermaphrodite, so when they mate, they're exchanging gametes between each of them and they exchange *** so when they line up like this, theyﾊ this is called a clitellum here, they secrete a mucus, helps hold the worms together and there's a groove here, so when this one discharges its *** the *** swims like and vice versa, so they get cross fertilization too. In terms of development we talk about this briefly we'll talk more about this in the redevelopment lecture we'll have a fertilized egg. This is from an organism that is a deuterostome they have radio cleavage the cells line over one another, bottom line is we have a cleavage we form a hallow ball, that allows cells to migrate inward from the outer surface inward a as you start to do that firm different neighbor interactions and you start to firm the 3 germ layers so they show the ectoderm, they haven't shown the mesoderm forming yet but it will form, and that's illustrated here, and red here that's a mesoderm firm. Yellow is the endoderm, the outside lose the ectoderm we'll talk more about that in the slide in the reproductive development lecture, be familiar we have talk about protostomes verses deuterostomes it means first opening, where the cells are migrating inward, that first opening become it is mouth in protostomes and in deuterostomes that first opening is a another open which is the ***. Okay. Sure. Protostomes, proto, first. Openingﾊ first opening is the mouth or stoma. So protostomes first opening in this gastrulation event to form this cavity or GI tract that first opening would be the mouth, eventually, so this if it's GI tract would puncture through here, you have a complete GI tract fact with *** if it was a deuterostome it would be an *** and the second opening would be the mouth. Okay. So proto first, mouth. Deutero first, ***. In terms of trying to keep track of all of this stuff again you can make various diagrams like this, be familiar with the features of these as you go through, for example we'll talk about the sponges we're going not separate the 3 forms but just sponges they lack true tissues. Okay. So that groups is actually called the parazoa(?), where as the metazoans, so this is parazoan(?)s, all of the rest of these would be you metazoans, we'll talk about the Cnidarians that have the radio symmetry. And the two groups we'll talk about protostomes and deuterostomes and then within here we'll have three groups we'll talk about here, the lophotrochozoans and then here the Cordaites and the [Indiscernible] and some time we'll subdivide these as well. So be familiar with these various things for the sponges, you book talks about this very briefly, so when we try to figure out that evolutionary history of these organisms it's tough do, if you look at sponge here, this shows they basically take water in, they filter it out for food and go outs the opening here's the illustration from your textbook they're composed of these cells called color cells they have a collar on them like this and they have a flagellum does it beats and creates a current, basically what they're doing is pulling fluid in, and as it passes through this collar, food gets capture and then ingested through phagocytosis and that's how they feed and then the cells, called amebocytes helps distribute the food. They do have a thin layer called the mesophyll. So basically, two cell types this seems to be the primitive form, we can seat protozoans and we think is the ant terrestrial group that gave rise to animals, we went from single cell to multicellular organisms so single cell to colonial and then to true multicellular organisms but they lack true tissues, Cnidarians they do have true niches but they only have two germ layers they lack mesoderm. They lack true organize inform that have true tissues but they lack mesoderm so they don't have the germ layer so they don't have true organs. So, sponges lack true tissues they do not have true tissues. When we go to Cnidarians they do have true tissues but they don't have 3 germ layers. Okay. But they have true tissues. So they have epithelial, they have some connective tissue, but they lack muscles, they have some cells that act like muscle cells but they don't have grouping they're muscle cells the groups we'll talk about, the classes, Hydrazoa, the jellyfishes, the box jellies and the anthozoa corals we have these things set up in the marina tanks to look at them, in the past what we did was I always told the students the marine tank will be one station on the exam so you had to be able to identify something from the marine tank, so anyway, I can't have a marine tank there but I can have photographs. In terms of the Cnidarians we'll talk about body plans they have a life cycle like this, the hydras that we're looking at in lab do not have this life cycle like this but there's a medusa form that's free floating when you think of jellyfish you have of that form and they have a polyp stage or sessile, they're not completely sessile they can move. And there are stages where we make gametes. If you can't make viable gametes that's the juvenile form. And sometimes if the juvenile form that can make viable gametes looks different than the adult form that does make viable gametes we talk about a larva stage so in human we don't talk about a larva stage because prepubescent kids look like a adults but they don't like gametes, when they take available gametes they are [Indiscernible] they can't vote but that's the biological definition. Good ways to organize this material. We give you charts to fill out in lab if you have the answers here you can transfer them to the chart if you want but if you go through the lab manual and read through it and try to come up with the answers for yourself you will learn a lot in the process of reading it. Okay. So anyway, please go through that as I mentioned there's only two germ layers there's no mesoderm, these are the body plans so we have the gastrodermis here, or seemed the endodermis we have the outside, epidermis and we have a layer between there in the case of the polyp form, that we're looking at, this jelly layer is very thin. But in the jellyfish that mesoglea can be thick, hence the term jelly. Okay. It just illustrates some of these. For the Anthozoas we have [Indiscernible] in the tank. The GSIs [Indiscernible] only in this phylum are these specialized cells called nematocysts and they have specialized structures called nematocysts. So I have a picture of this, right here. So they show this here, that's unique toﾊthis phylum and in here is a nematocyst they can release toxins so when you hear of the poisonous jellyfish, what's happened is they discharge these the nematocysts they have fired and there's toxins there and the GSIs should demonstrate this in the tank. The nemane(?) will discharge the nematocyst, and you watch them cringe in pain the ones we have aren't poisonous, you can't feel it but you know they injected it because if you move your finger you will move the tentacle, but I have in the past struck my tongue down there, and they will discharge into your tongue and your tongue's more sensitive so you can feel that and it numbs a little bit, but I don't do that anymore because the rumor was I was French kissing everyone at the meet, I don't know how rumors get started. Okay. Anyway. It's amazing how rumors get started. Here's the polyp form of the hydra that we're looking at. In the lab we'll already have them in dishes, you'll pull them to your microscope and look at them, just want to warn you that the act of moving them will result in a defensive posture where they ball up and they will ball up for a minute or two and then they will open up and you can see things but that's a defensive measurement, response so this shows what's called asexual reproductions you see this new organism budding off here, identical to this parent so it's a asexual reproductions. The gastrovascular cavity is indeed in connection with this cavity soﾊthat's how you can feed this developing individual. This illustrates reproductions the testees here, ovary here, so we're making *** there, eggs there, here you see this gastric vascular cavity, here you see the gnat toe sites the way to see them, use the lighting from the lumenators but have an angle and you will see cells glisten about and those are the gnat toe cites, they're hard to see, we have prepared slides to look at. When you see this cross like this, we have prepared slides, you will see this is very thin you will see the gnat toe sites here they tend to be round we have a video we'll show you in lab that you see discharge of these in the video, here's the gastrodermis here, what happens when they feed, so you're going to take and speed them some bine shrimp, since they don't sense it they have cells that contract like muscles, and then they will basically force that brine shrimp into the gastrovascular cavity so they open their mouth wide, they ingest the shrimp, close it off and once they closed it off it's effectively close to the outﾊside environment then they will dump digestive enzymes into the gastrocavity, so they have extracellular there, so they have phagocytosis. We do not have phagocytosis in humans but we have that cellular digestion, we close out our GI tract, we start breaking it down, so this is extracellular and intracellular ingestion and the advantage of this is you can capture large prey very quickly and oftentimes when you're capturing prey you're defenseless because you're focused on feeding. Look at the cross section, try to identify various cells there, look at the various slides, things that we have to identify the very classes, on the lab exam I'll probably have a few images ofﾊthings and identify the class, and I'll probably have Cladograms, and may have blank diagrams and you to pick the correct Cladograms and put the correct ones on the Cladogram. The flat worms, we're talking about 3 classes, [Indiscernible] the flutes and the tapeworms and we use to have a lab on this, where students would get liver tissue, and the students are basically cut out the various flukes in there and they're definitely there. Okay. So for this, again these charts, I'm not going to read through this, but I do want to point out we have 3 germ layers and we have bilateral symmetry, and advantage of by lateral symmetry often times we see cephalization, because there's one end of the organization that's in the environment first so if you have a flat worm that's free living, like this, we've talked about cephalization the term we've see it illustrated here so if this is a flat worm we have these things called eye spots, they do detect light they're called eye spots this is probably the one time you don't want to use direct illumination or side light because they want will want to swim away from the light. But this is the anterior end this, is the end that's going to enter into a new environment so we want to have more sensory here in that new environment to detect it is it appropriate environment, etc. So we see this bilateral symmetry and we end up with a, you know, left half and a light half. Okay. This is illustration for flukes, how many of you are interested in public health? So, with public health there's issues about sanitation and stuff like that, [Indiscernible] is the second most revel lent disease, malaria there's more, but huge cost in terms of economic cost, huge devastation in terms of personal being in that, so there are issues about sanitation and it's kind of interesting because they have fairly complicated life cycles so if you think about this, we have a fluke that infects a human, the immune system of the human is trying to attack it, they reproduce sexually so they're go row lease eggs which will go through the development have [Indiscernible] larva and they don't look like the adult, they infect snails, they have immune system as well so the snails is going to I tack the parasite in here, basically, and then from the snail we'll get say asexual and the larva come out and pen strait here. Soﾊthere's issues about contaminated water, things like that. So in terms of another group, the tapeworms, and probably cooked meat, not fully cooked and we have some example of tapeworms in lab, and one of them came from basically the evaluate of [Indiscernible] this, is an illustration ofﾊ there's a museum in Tokyo on parasites this is one tapeworm. It goes on and on and on. This is how they attach to the GI tract, they have these hooks that basically hold onto the GI tract, and as they're in the GI tract, people that have them they say they can feel them wig until the GI tract and there's they absorb the nutrients and then they become a reproductive machine and now, I don't know how many of you have heard about the radio about the lap bands and will wrap you and remove 16 inches in in 2 hours from your waste. So theﾊ it has always existed those kinds of advertisement so this is an ad, basically they told tapeworm eggs, as a diet pill. You lost weight, not false advertising, I love this right, eat eat eat just what we say, you don't have to exercise, you'll lose weight, take this medicine, right. So, no diet, no baths they didn't like taking baths no exercise, no ill effects that might be false advertising, so come up with a catchy slogan they don't do this anymore. That I know of anyway, but other chemicals you can buy they probably as bad for you, yes, question? >>STUDENT: [Indiscernible] >>INSTRUCTOR: Okay, so the tapeworms, what happens is, once they're in you they're going to try to reproduce sexually so you're going to be making fertilized eggs you pass them through the GI tract, so what happens is, you might hear these rumors that a person has a tapeworm so they starve themselves for a couple of days and they get a glass worm and the tapeworm crawls out and it doesn't happen that way. Basically it would be passed in the feces the medicine they take for this, and you can read accounts onﾊ I mean this is the beauty of the Internet you can read accounts of people who have this medicine the medicine they give you it effects ability to attach, so if you can't attach you dissipate it with you feces, yet they're defecating yet they're 20ﾊfeet long so it takes a while. Don't visualize it. There are times you want to visualize biology, otherﾊtimes you don't. Free living flat worms, there's those eye spots, they want to move away from the light which is why I don't have great illumination there. Here shows you some various images of various organ systems here, the digestive system here, they actually people who study these areas, classify them based on how they branch things like that, realize this [Indiscernible] cavity branches anteriorly and posteriorly on each side. This is a pharyngeal pouch that allows [Indiscernible] allow it to go in and out. So as I make a cross section through here, right dead center where that pharynx is, realize there's a pouch here, that allows the pharynx to go in and out that is not a coelom, it's like your oral cavity it's a cavity but it's not a coelom it's not internal. Okay. That can be very confusing, the other thing that's confusing and I didn't name this and I understand why it's confusing is it label this the mouth but this is the opening of the pharynx because food is going in here, but this is opening so they extend the pharynx out to feed, we'll do a feeding doe mow, so you do it of the hydra, here, we're looking for [Indiscernible] slides, plus a feeding demo with the egg white, you will see them extend the pharynx and suck the egg white, we have stained slides so you can see the digestive system. Increase number of neurons at the anterior end it looks like a nerve ladder. In terms of excretion, they have these structures called protonephridia, remember this is a solid packing here there's no coelom, but that does not mean they don't have fluid between the cells so Dr.ﾊWeisblat mentioned this in lecture today how cells tend to be hexagonal, and what happens is, we don'tﾊ we actually have some space here, and this space between cells is called: The interstitial space filled with interstitial fluid. And that's filled with fluid. So what's happening here is you're pulling in interstitial fluid, the fluid between the cells, and you pull it into this tube, and the way that works is they're flagella here that [Indiscernible] they didn't have great microscopes, so when they saw this they thought it looked like a flickering of a flame, so they called this the flame cell, they're flickering they create a section effect of that pulls fluid in, interstitial fluid into the tube, it's effectively outside of the body, it's taken up or excreted into it. And that remaining solution gets excreted out and opening on the surface. Okay. And you see this is repeated through out. Okay. So that's the protonephridia and there's no actual direct opening into the interstitial space. >>STUDENT: [Indiscernible] >>INSTRUCTOR: Okay. So the moment it's in this lumen of this basically tube, it's outside of the body. Because a bacteria, bacteria can easy go through this opening, up, up, up, and never crosses the cell membrane. So, to be inside ofﾊthe body you have to cross a cell membrane. So once it's in the tube it's effectively outside of your body and you take things up or secrete into it you see the same is true with the nephron, in terms of the reproductive system they're hermaphrodites, so they're produce both types of gametes in a cross section like this, I want to point out again this is the pharyngeal cavity here, the pouch, that's not a coelom. There is a lumen of the pharynx that's the inner part of the pharynx and that's what led to the GI tract here. Okay. So, the lumen here is here and it branches out to theﾊ I should gastrovascular cavity. Okay. When you make the cross section you will also cut the gastrovascular cavity, and the connection like the muscles they use are long nude tall and circular muscles the best way to recognize is if you have circular muscles that go around the circumference like this in a cross section like this, when you see the cells, the muscles that go around the circumference are going to look like this... So the circular muscles look like that... The longitudinal muscles are just dots in that direction. So, some GSIs say, circular, has any in it, which means circular muscles are inside or internal, don't write this down because it's not true. Okay. And they will say long nude tall, which means outside it's not true. Depends on what you're looking at, so just remember the circular muscles will look like this in a cross section and the longitudinal muscle also be dots. The longitudinal muscles will look like this and the circular muscles will look like that. So it depends on the section you take. So be sure you can identify that and I'm pretty sure if I will have an illustration on the lab exam when I ask you if it's longitudinal or circular muscles. Here's the slide you'll be looking at, there's the pouch there, there's the lumen and there's longitudinal and circular muscles. Make sure you can identify them. In terms of the annelids. Polychaetes and the leeches, so those are three classes you'll dissect and earthworm here so this is your first dissection in this lab with the earthworm and then you'll just look at demonstrations of diversity here. We'll have feeding demonstrations of leeches in the lab so basically what we'll have is intestine we'll fill it with blood and have leeches feed and see that they engorge themselves these have a true coelom it's quite large and that's taken advantage, when these leeches feed because they have a large coelom they can fill up the digestive system with a large amount of blood because they don't get to feed for very long they fall off they're host oftentimes and here's the charts you can fill them out for yourself it's the best way. Here illustrates the earthworm, here's the clitellum here, this is the posterior end here, this is the anterior end here there's a mouth here, the anteriores end is short relative toﾊthe clitellum, when it rains hard, the reason why they're coming up to the surface in and you see the burros in the ground and the cast from them crawling through the soil is because they're basically drowning they're spacing between get filled with water so they can't get enough oxygen so they have to come to the surface to breathe. I don't know if you've gone night crawler hunting? Not very many. All right I grew up in the Midwest so this was one way I made money as a kid. I would go night crawler hunting is the best part is they're mating, one hand you get two earthworms they're also distracted so they don't sense your vibrations as well. All right. Here's the dissection that you would do it's two cuts it's very quick, the dissection takes less than two minutes, one cut laterally, from side to side, transverse cut, hold the scissors, transverse and then cut from the posterior to the anterior all the way up to the mouth, lift the scissors up as you make the cut if you don't lift them up as you cut you will hit the internal organs. When you do It can like this you will see something like this we have the GI tract that runs from the mouth all the way down to the *** now we have a true GI tract with a true mouth and true *** and we get specialization along that track. So we have a pharynx that muscularize to pull in foods, earthworms open they're mouth and crawl through the soil, lifting leaf debris, etc. They don't have teeth so they ingest whatever is in they're path they pull it in with muscular pharynx and then they have a crop here, that's storage so they can it's equipment to analogous to our for storage, and they have a gizzard here, it's highly muscularrized. Because it is so highly [Indiscernible]. We'll see bands of muscle on it and you can see the structure easily and it basically just the muscle contracts back and forth, like peristalsis and any bits of sand in there, two bits of sand gets pressed along with each, and there's leaf fragments it fragments that. So they're doing the same thing here, stone ground. That fragments enough so in they're intestine they can release digestive enzymes and absorb the nutrients. As long as we have this, we see here the circulatory system, so they have a circulatory system these things are large they have a large volume so we have to have a circulatory system with the flat worms that [Indiscernible] diffused across the surface we didn't need to have a circulatory system to distribute the nutrients they diffused right out of the [Indiscernible] cavity. In this case it's we have to have a distribute nutrients, distribute gases, they fleet across the surface into the circulatory system and in this case its a closed circulatory system so the term we use is blood for the fluid within it. Not hemolith but blood, so blood gets circulated through out, we have a dorsal blood vessel that's actually your landmark for the dissection. If you notice here the dorsal blood vessels here, okay. So make sure when you do your cut you're cutting from the dorsal surface to cut from the ventral it will not match the diagrams at all. So dorsal blood vessels are your landmark but they go to a [Indiscernible] blood vessel, you see that in a diagram here, all of the circular blood vessels contact a bit but not a lot in the anterior end there's 7 or 8 of them that contact a lot more than the rest so these are called the pseudoheart, they will beat for several hours the earthworm is dead, there's no neural activity in the brain, but the heart muscle and that will still beet for a long time. But itself is dead. So you'll see blood being forced through the circulatory system, anterior and then posterior. If you cut it, you'll lose a little blood it won't squirt, the other thing is when you cut this, hold it in your hand, not in the pan, a lot easier to hold it in your hand and make the cuts and then when you actually do the dissection you're going to completely submerge the earthworm, completely with your fingers pin out the earthworm to the side and that ringers will calls causeﾊall of the structure slope so it will be easy to see. So, on the GI tract we talked about that we talked about circulatory system here it shows you a segment. A segment another way for that is sew mite. So confusing terms. Septum is the thing that partitions like your nose, so in this case the septum partition the somites. Okay this is a accept item that partitions them. Here we see the GI tract along here. There's this infolding, to increase surface area it's called a typhlosole. We see in this case what's called a nephridia, there's a opening in one segment here this, is a huge coelom, so coelomic fluid gets pulled in here its a true opening, in the flat worms it was proto, this is meta. True opening here. Again, once the coelomic food is pulled inside, it's effectively outside the body and it has passes through the tube it will go out through the surface. And that's shown here, it's not too important but this opening is the anterior segment comes through here, blah, blah, and eventually out and you modify the contents in this tube. Since you're taking up things into that, we see we have a capillary bed around this to absorb the fluid, and you will see this clearly in the lab because with each of these, you will see blood vessels you will see the redness of the blood. Okay. Here's a cross section like this... This is idealized, you won't see this in a cross section, the reason I say idealized we see [Indiscernible] and they use that in the soil. We have a live earthworm in the lab, pull it across your hand and what it's going do is it's going stick out it's going to anchor and if that doesn't work try the back of your hand that's more sensitive, if it doesn't work, try your cheek. It's just an earthworm. Okay. And then I won't everyone tell you to try your tongue baa because that's even more sensitive. I have a nephew he loves eating worms. He likes it better than candy. So as a kid he would always eat earthworms mom would ask him, not my child, but ask do you want candy or earthworms he just loved earthworms now he wants to charge me to video tape him, I don't think it is fair, that's the way it is. So here's a sitay(?), they anchor in you can fill that if you pull it across your hand, on the video you'll see them actually sticking out their sitay(?) anchoring as their trying to attach to the sub trait, so they again have, what type of muscle is this here? Circular, it goes around the circumference, so imagine this was a balloon and it's like this, if I have circular muscles like this and I squeeze it what happens to the dimension of the balloon it gets bigger anterior and posterior so when the circular muscle contracts like this, which means at this end it's now elongated it can anchor its the soil and then it relax it is circular muscles and contracts its longitudinal muscles when it does that it shortens the segment so it moves forward so that's how it moves forward by altering contraction of the circulatory and the longitudinal muscles in conjunction with [Indiscernible]. Here's shows you the GI tract here, that called the typhlosole, the surface area. And we see some yellowish cells that line on the surface of the intestine called cholerigenous cells they're liver like in function. Liver detoxification. Formation of nitrogenous waist. And then ventral, we have the ventral blood vessel but we have a ventral nerve cord and that will be white in color. So make sure you can identify that, there's the dissection. >>STUDENT: [Indiscernible] >>INSTRUCTOR: So the question is, what is the function of nephridia, it's the excretory organ that regulates osmotic balance, specific ion concentrations, calcium, potassium, sodium but it raise water balance so it's equivalent, so our nephrons or kidneys, okay. Here's the actual dissection, here you can't tell this but this is submerged underneath ringers. We have beakers by the large containers of ringers. We're where squirt bottles at your station but the squirt bottles have to squirt away any bubbles or maybe you accidentally cut in the GI tract you can squirt it away but don't unscrew the lid. So walk over, grab the ringer from the big container. Here's the GI tract here, going from the pharynx, the esophagus to the crop for storage the gizzard. Highly [Indiscernible] looks like if you remember the diagram in Campbell it looked like the rest of it but it looks different: Here's the intestine here, there's that yellow tissue. The dorsal blood vessels here there's the pseudohearts. You can see it going over and down. Okay. Here's a close up, it's actually been cut accidentally this was the crop here, for storage. But you can see actual the bands of muscle that go around. So we see here that the bands are going around the circumference butﾊ so that you can contraction, so help turn that there's the GI tract off in this way that's the [Indiscernible] and cells. Here's looking tat anterior end of the earthworm, so we see the pharynx. And that's here. And we see these two white structures here. [Indiscernible] tend to be white in colorﾊ (No sound). That's called the suprapharyngeal ganglia. Suprapharyngeal ganglia. Ganglia clump in neurons, pharyngeal and supra for above. We can't see it but there's the nerve cord underneath. I do want to see this all of the striations here, so remember, that pharynx has to generate a force to be able to pull food in, right.ﾊit has to be anchored to something to generate that force. Just like, you know, when you generate forces with your muscles they're anchored to bones things like, that so that's how you can develop a force there. So this is an outside body wall. And we have that tube inside of the GI tract, so that pharynx in this case is anchored internally to the outside skin and that's all if I would with a coelomic fluid, and so we allow the pharynx to generate a force to pull food in, through the esophagus and down. Now these are the sum natural vesicles here so here with testees that are producing the ***, the ovaries are here as well we can't typically see those but we can anterior middle and posterior vesicle that we can't see that's not in the diagram here, these structures off to the said, they look different in other, and different in shape are the ***. Or seminal reciprocals, remember I told you the worms mate with one each it has to accept the *** it receives and make its own ***. So these are the structures that it will store donated ***. It receives *** donated to it, and it will transfer *** within it to the other individual and those *** are produced within the testees. Okay. And then this just shows you here, we didn't see the anterior, middle and posterior [Indiscernible] vesicle there. Here's those seminal reciprocals are ***, same thing, these are called sifrous(?) glands here they can be hard to find, so I want to give you the orientation, heads over here, anterior, we had the pharynx going the esophagus these [Indiscernible] glands are called esophageal, but they're also called calciferous meaning they play a major role in [Indiscernible]. One helps with in terms of location, the other function. Here we've cut into the GI tract, there's that infolding in the typhlosole, heres just food debris within there. You can see this there's a lot of blood here because we've cut blood vessels, there's a metanephridia here, let's see if I can see one here, we can see one here, right there that blood vessel that starts with the nephridia, other here, there's blood vessels there, there's another one there, there's some in each segment so you should be able to see the metanephridia, the other illustrations you'll do a dissection look at prepared slides and look at live stuff that we have. We have polychaetes in display this is a pile worm, with have feather duster in the marine tank, these use to be common questions from the GSIs, they would ask you to identify what class it belongs to it's a polychaete and it belongs with the annelids. And they have these projections from they're surface called parapodia that they use for gas exchange, so the other earthworms are exchanging gas for the entire surface, and they can actually use them to move a bit and they help circulate fluid past. Now, there's a lot of pandemics, etc. but it applies to pretty much erg, I don't know if you've driven across the board and you have potted plants in your car, you're not supposed to do. They will typically pull it out and throw it away because you have various nematodes like that in the soil. This just illustrates here, there's worms now, just earthworms, so it turns out that the earthworms we see out in the soil were not common to the U.S., you know, a thousand years ago but they've pretty much become common now, and we modern humans have adapted in the last 400 years or so to the this. But flow's new earthworms invading environment and they're changing the soil topology, which is killing off species of trees so forests are diagnose because of this, so there's issues of bringing in soil and stuff like that, that's why they sometimes say if you boat in this lake, you to wash it off thoroughly, so you don't transfer muscle from one type to the next. With current systems easy to do that and it's hard to erratic things once you're established. There's lots of ecology classes you take. (Lost Gatherplace) >>INSTRUCTOR: So I do want to point out that next week we have lecture, so that's on the 5th, we'll have the invertebrate 2 lecture, so the schedule is as follows, I believe, I want to check again, but we'll have invert lecture 2 next week. The 12th is a holiday. Veterans Day, so we won't have lecture that night, so we have to watch the webcast from spring 2012 we do have lab this week. Sorry. This is what happens in fall, we have lots of holidays that impact our schedule. On the 19th, that's a Monday, we don't have lab lecture. This is Thanksgiving week. On theﾊ yeah, it's not the last week of Thanksgiving, on the 26th that Monday I'll have a review in an hour, slides asking various questions and Wednesday the 28th you take the exam. So that's the schedule. We've never had it happen like this, where Thanksgiving is falling like this so you have several weeksﾊ two weeks to study pretty much for just lab exam 2. And I do think this is one exam where if you spend lots of time memorizing these things, identification that it typically is rewarded it's not real conceptually driven so if you say to me, what do I need to do to really well, it's kind of in your ballpark, a lot of studying, quiz each other, things like that, so with respect to mollusk, the classes we'll look at. [Indiscernible] the gastropods, the snails and that. Now, for the bivalves we had a demonstration of this, so remember we had demonstration of the heart we'll have a clam that's dissected the GSI or [Indiscernible] will demonstrate it and they have been instructed to finish those demos within the first hour of lab. So, that that gives you a full hour or so to go over and look at a clam on your own, look at the brain structures, ask each other, people are asking you know does it helps to take digital images? Sure if you want to take digital photos, label it things like that. Feel free to do so. We have not seen a big increase in scores with the advent of digital cameras, sometimes what happens is you spend more time trying to label every image, you might have been better off just to spend 30 minutes. But, I don't know what's best. Okay. So anyway these are the class it is features that you'll see, mollusks and traits, that secretes the shell, the shell is usually made of calcium carbonate. We have a foot for movement for gas exchange, some people sometimes call them gills, but in fact they're filtering out food as well so that's why they shouldn't be called gills because they do both gas exchange and filtering food. And we have a [Indiscernible] for capturing food. Okay. So, in terms of the clams they don't have a [Indiscernible] because the antennas replace the function. Here's the charts here. They have an open circulatory system, this is just illustration, some of the diversity. The cephalopods we use to do a squid dissection we don't have time for this. We've lost two labs, relative to what we use to teach in this part of the course due to just changes in the calendar so we no longer do it we use to. Octopi here, interesting story Is about cephalopods in terms of they're behavior and the terms of complexity, kind of interesting story there was this lab that had these marine tanks and they're fish kept dying off and they couldn't figure out what was going so they decided to set up cameras, I think they thought the custodians for taking the fish home and cooking them, they set up camera, and what happened was, an octopus would crawl from one tank over to the other tank and feed on the fish, and then there was no protective substrate to hide underneath so the octopus would actually crawl back to the other tank so it would hide underneath the substrate for the protection. And I want to believe it if I hadn't seen the video. So, poly[Indiscernible] they usually have plaits like. This. [Indiscernible] are naked snails they don't have the shell like this, remember I mentioned that nematocyst, from the Cnidarians, these actuallyﾊ it's pretty amazing, these things feed on Cnidarians they ingest the Cnidarians into the GI tract and somehow food through evolution they managed where they take the [Indiscernible] and embed them in they're own body tissue for protection so they're not making the nigh toe cites they ingest them and then the cells migrate into the body wall that's pretty amazing that's how they get the protection, often sometimes they have the toxins by very brightly kin and that, here's a squid here, cephalopods, this is the head, they have image forming eyes here, a lot of the things are study in terms of neuronal trance mission things like that, they actual will have parental behavior, this shows you a squid here, they're different genders so there's male and female squid this is fertilize egg mass here, effectively puffed up to increase the surface area for gas exchange and when she'sﾊ when they're threatened she collapse that egg mass, holds it in her tentacles like this and jets off for protection. Now you might say why study squids and things like that. These are articles I captured here, so, squids have a beak what they used it's modified rad la and they use this beak to tear apart food so when you see the stories of the giant squid and that, sometimes you will see a whale that has huge suction harks where they grab with the tentacles so they're trying to use their beak to grab food there they'reﾊlooking at how this beak is attached to design for devices how do you attach them to the individual so you don't get as much tissue damage on the individual, how can you improve the connection and stuff like that, here at UC Berkeley they're studying the amazing behavior of the squid, kind of interesting that's here at UC, here's a scallop here, light sensing on the periphery here, here shows you the shells, the GSIs will do this illustration for you, we have the shell here we have a right side and a left side this, is the right side of the shell this is the left side these would be together normally, so these are sometimes called valves that's why it's called Bivalvia, two shells. This is anterior, this is posterior, so in lab the GSIs will illustrate with intact clam, so they use the foot and move as you look to the right, so that it makes anterior, posterior, here's the shell here, the mantle was attached here, so you can see a line where it actually attached called the paleoline, where the mantle is attached, the mantle secretes the shell outside for protection. Pearls are when the mantle and some species are better at it than others where the mantle has been irritated by a piece of sand or something like that, typically and they wall it off the irreproducible station, like sometimes when you get a sliver, they do with the calcium carbonate and that's that pearl. Cultured pearls are what they do is go in with this particular species, specific sides in there and then the glass beads get the shell and that's what I they're so uniform in shape and that. So anyway, and also part of the mass of that pearl is mass bead. So you automobile to be able to tell from the left side, right side. On the scallop, there's a huge scar here where the anterior [Indiscernible] muscle was attached there's anterior muscle here. Adductor muscles add to the midline, if you're at the gym, goes the legs that's the adductors, so in this case they use adductor muscles to close up so if a star fish is trying to feed on this it uses the adductor muscles to close up and then the star fish would try to open it up to feed on it. In terms of how the clam itself feeds, it's a little confusing perhaps, so let's just go over this illustration, here's the foot to this would move to the left. When they closes off its shell, when it uses the adductor muscles to close the shell it's water fight. So that mantle cavity is now water tight it's open to the outside environment though by two siphons there's an incurrent siphon and excurrent siphon the incurrent is veneral the excurrent is dorsal. So on the ctenidia on the cilia, on the cilia, [Indiscernible] this is a water tight system that create a current, if you're in a bathtub with right hand you go like this constant you create a current that goes all the way around so, the same thing happens here, when the cilia beat they suck water in the incurrent side of it must has the ctenida, so that water gets [Indiscernible], and then it goes the GI tract. And the heart is on the dorsal aspect and the *** is just this portion here. Now, I've connected this figure in the lab manual, but they use to have the *** coming off the heart it doesn't work that way, *** comes off the GI tract, mere's the actual dissection here, we're looking from the ventral surface, ventral surface. So, this is anterior here there's the foot, so it moves toﾊthe right as you view it. This is the incurrent siphon so when it closes up there's the mantel edge there, mantel edge there, when it closes up it's water tight we can't see the cilia on the ctenida here, but when they beat they beat such when they create a current when it sucks fluid in the incurrent, ventral, in here, past the ctenida, so back to the plane of the screen here back out that way and we cant ever can't see the excurrent side. So that's how it's filtering food, food gets captured here it gets transferred up to the mouth and here, there's some structures here that [Indiscernible] transfer into the mouth there's an opening there. All of this mass here, and here, we call visceral mass, it's not meant to be confusing it's just lining we talk about appendages, heads, arms and legs a and the torso instead of calling it torso we call it visceral mass. Okay. Here's the adductor muscle, here this is anterior or posterior? Anterior because it's anterior and posterior we can't see we can see it looking a at the dorsal aspect but we're looking ventral here's that mantel if it was forming a pearl or something like that we would have an irritation there it could be sitting in the shell there and that would be the pearl there. Here's looking from the dorsal aspect. And here's the excurrent siphon here we've cut it normally within the see it here, the incurrents over here, so the two siphons are right on top of one another with incurrent ventral, excurrent dorsal. So normally this would all be sealed upﾊ we're looking at the ctenida here from the dorsal aspect it would be coming up towards you from behind the board up towards you, that's a filtering process and forced out the excurrent there so if you're going to dump your waist, you want your ***, this flap here in the excurrent siphon not in the incurrent siphon. Okay. Like wise if you dump gametes you dump them downstream, the hearts up here have a bright orange structure and they're hard to see.