Lophotrochozoans

Okay, everyone in this lesson on invertebrate organisms, we're going to be specifically talking about Lofa tro ca's Owens. And while they have, like a really crazy name, I promise they're not that terrible. Low Fetrow Kozo ins. That's a super Fila. So a super Phila is gonna be one big group that contains many other Fila. So in this super Phil, um, sorry. Phylum is the singular Fila is the plural. So in this super Phil, um, we're gonna have many different other Fila that we're going to talk about that fall under this category. So Lofa Tro ca's Owens have a really crazy name, but it's kind of, um a smashup of two of the main types of organisms. As you can see, we have low for its or one of the types of organisms we're going to talk about. And then we have TRO co fours, another type of organism. We're going to talk about so low fat. Rocca's Owens is a combination of those two names. Now these invertebrate organisms are bilateral. Remember, that means that they're mirror images. So we are bilateral organisms. If you cut us down the center, we have a mirror image on each side. So were mirror images. We have that kind of symmetry their protest owns. Remember, that means an embryonic development. The mouth is the first cavity that is formed in contrast to do Douro stones where the anuses, the first cavity that is formed. Many are Cee Lo mates, meaning that they hate this around. This means that they have water inside of their bodies and they're using that water pressure to keep their bodies upright to give them structure like our solid bone skeleton gives us structure. They have a water system inside of their bodies that gives them structure. So now let's talk about some specific types of low fat. Rocca's Owens. We have the trophy fours thes. They're gonna be any types of organisms that have larva with a ring of cilia around its body, and this is gonna be used for swimming and feeding. I'm gonna go out of the picture because this image right here is going to show you what a truck for actually looks like. This is a tro ca for larva. Remember that that is the adolescent stage or the non adult stage of this developing organism, and you can see here that I'm highlighting in yellow this ring off cilia and this ring of cilia is utilized. Thio, bring food into the larva and help it move around. Remember, whenever we learned about cilia, these air gonna be projections from the cells and they do actually have motion. They do have movement. Some examples of organisms that are truck a fours are going to be molluscs. And analysts were not going to talk about molluscs or analysts in this particular lesson. But coming up in the next couple of lessons, we'll definitely talk about molluscs and analysts. So molluscs are going to be things like oysters and clams and scallops. And analysts are actually segmented worms like earthworms. And they are trick of force because they have a larva with Sicilia ring. Okay, now the stroke of fours have an elementary canal. You have an elementary canal and these air going to be digestive tubes with two openings, a mouth and anus. That's very simple. That's common to a lot of organisms. Now let's move on to the loaf of for AIDS. This is a different type of organism thes. We're going to be animals with a low four Ah, low four is gonna be a really specialized feeding mechanism. So a specialized structure used for suspension feeding, and we can see that in this image right here, you can see that it's it looks like a little crown off these little cilia or these movable projections. And commonly you'll see this structure called Crown because it kind of sits on the organism and it will move its little. They kind of look like fingers to me. It will move its little fingers and grab food from the water that surrounds it. This is going to be a loaf, 04 And it is a really interesting feeding mechanism that grabs food and then pushes it towards the mouth of the organism. Okay, so some examples of Lofa Force are gonna be ect approx and break your pods. So ECT approx are actually what you are looking at here. These air going to be coral reef building animals, but they're not coral. Okay, we will talk about coral and a bit coral is actually a night area, not a ecto products. So whenever you think of coral like an actual coral organism, those air not going to be ect approx while act approx do create coral reef structures. Um, they actually kind of look like moss. So if you you can see here that it kind of looks like a hairy little structure that might look like a patch of moss. If you saw a whole bunch of these organisms together and they look so much like moss that another name for Ecto proxy is going to be Brian Zones. And if you remember, or if you've gone over the lesson on plants, the name for Moss is Bryan fights. So these are Bryant's Owens. They look like moss. So those air two names for the same thing act approx and dry zones. They're the same thing, but they do look a lot like Moss. And they some of them do have these hard exoskeletons that allow them to build these reef like structures. Now, there's also break yo, pods brake. You pods are going to be these animals right here that you see, with the long, kind of foot thing sticking out, they look like molluscs. They kind of look like bivalves, but they're not, um they're not bivalves, even though they look a lot like bivalves, so break your pod sobre Keogh. Or, um, let me see e did that. Wrong break, Eo, actually, is ah, word that means arm pod is actually a word that means foot. So their name actually means arm, foot and their arm foot. You can see right here is utilized to hold them in place to give them structure to give them, um, the place thing toe hold onto. They use this arm, foot toe, actually dig into the sand or the dirt and hold themselves in place. And, no, it's not called an armed foot. It does have its own name, and this is actually going to be a pentacle. So they're pentacle or their arm. Foot is used to hold them in place. They're mostly marine animals, but they're not bivalves. Even though they do have two shells that close, they're actually not bivalves. Bivalves will have a left and a right shell, and they commonly open their shells like this. They have a left and a right. However, break. Your pods have a bottom and a top shell, and they commonly open their shells like this and the foot will stick out the back. So that is what a break you pod is which can kind of be confusing with bivalves. But these air low food truck is Owens. Okay, so now let's go down and let's look at some other low fat cocoa zones, which are pretty interesting. So now we're going to talk about the Philip Plata. How men? Thieves. They also have a really crazy name. But most people generally just call these flatworms and flatworms. There's a ton of different types of flatworms. They come as salt water. They can live in the salt water. They can live in fresh water. They some of them are even parasitic. A lot of human parasites are actual flatworms and flatworms are a cell, a mate, meaning that they have no body cavity, no internal body cavity there, triple of last. They have three cell layers and they have a rudimentary digestive system. And what this means, rudimentary digestive system means that they Onley have one digestive opening. They only have a mouth and food goes into the mouth is digested in their digestive system and then waste comes out of the mouth so they only have a very rudimentary digestive system. Now they are some of the simplest bilateral organisms, and they lack gas exchange organs. They don't have lungs and they don't have gills. So what they do is they actually do the elimination of nitrogenous waste and gas exchange across their body surface via the process of diffusion. So because they use diffusion, that means they can't be incredibly large. So most of these flatworms won't be very big at all. The maximum size, I think is they get, like, maybe this big, and that's because they have to do diffusion and they don't have circulatory system and they don't have a respiratory system. So these organisms can perform sexual and a sexual reproduction, and they are very commonly parasitic, so some require hosts to reproduce. So, for example, um, tape worms and flukes, which are to human parasites, are going to be flatworms. They're gonna be in the group plateau. Hellman thes and you guys can see a saltwater flat form right here. Okay, so now we're also going to talk about road offers. Road offers belonged to the phylum rot Ifrah, which I will write for you. They belong to the phylum rot Ifrah and road offers are pretty cool. They are actually gonna be. I'm standing in front of a picture of one here. I'll let you guys see it. They're actually going to be microscopic organisms. Mhm. Well, my buttons not working. But anyways, you can see here they're actually going to be microscopic organisms. You can Onley see these under a microscope, and they're also gonna have bilateral symmetry even though they don't really look like it. They do have bilateral symmetry. So do flatworms. Remember, that means that if you cut them in half, they're gonna have mirror images of one another. They are pseudo cielo mates, meaning that they have, ah, body cavity. But it's not a true see loan that surrounds their digestive tract. And they're going to be named for the ring of cilia around their mouths, which you guys can see is this structure right here, that ring of cilia around their mouth that is used to push the food into their mouths like we already talked about. Now they're going to utilize parthenogenesis. This is a very unique way of reproducing. It is an A sexual reproduction in which females produce unfertilized eggs that rise into more females. So basically what it is is the female is going to be, um, making clones of herself. So she's gonna be making mawr females, and they can use this. A sexual reproduction called parthenogenesis. Thes road offers air also very, very important for freshwater ecosystems. They are mostly freshwater, and they're going to be one of the components of zooplankton that are going to be very, very important for all the fish and crabs and different things that live in freshwater lakes and streams. They're going to need these road offers to eat. So their major food source Okay, everyone. So now we're going to talk about Mawr invertebrate organisms, and we're going to move on to molluscs. Okay, everyone, let's go into our next topic.

molluscs are kind of the star of the show for the low Fetrow cause Owens. And that's because they come in a wide variety of classes that have bunch of different morphological features that air quite diverse. Now, molluscs as a whole are kulum mates, and their bodies tend to have these three characteristic pieces what we call the foot, which is basically a large muscle. Usually it's gonna be used for movement. We'll see pretty interesting exception with creatures like squid. So anyways, this bottom piece right here on our example that is going to be the foot. We also have the visceral mass which basically the internal organs of the organism and its external gills. And that's all this mess here. This is our visceral mass. Just gonna right VM for visceral mass. And the cavity inside of this is called the Chemical. And it's named for the fluid. Uh, inside of it called him a lymph, which is ah, similar to blood. Basically So uhh the he Michael that's the cavity, and it's filled with that fluid that is gonna act similarly Toe blood and that fluid is actually going thio directly bathe the organs because these organisms. Mostly there's gonna be an exceptional talk about later. Have a new open circulatory system. So, uh, the all right, You know, the fluids that air going thio carry gas is to the organs are not going to move through veins or arteries or anything like that. It's just kind of floating around in the coal. So, uh, the feeding structure briefly, I want to mention it's part of the visceral mass is called the Regula. It's at the anterior end. What you could, I guess, kind of think of like the head. And it's a little hard to see in this image, but the Rachael A is right there. Basically this'll feeding structure is it functions kind of like a rasp. So, you know, think about unum brace, Ivo edge or abrasive surface kind of rubbing on the food to break it down like a grinding type way now. Uhh. Not all molluscs have a rad, Djula. Um, but many of them do so that's why I mention it. Here is sort of a general feature of molluscs. The last structure that's common to molluscs is the mantle, and this is basically just a covering for the visceral Mass, so you can see that it's actually this layer here, this layer just under that outer shell in the picture that is, he mantle. And it often forms a hardened calcium carbonate shell, which we can see right here. This is the shell, but this is not always the case again. We'll see some exceptions. So it's worth noting that in some species there's something called a mantle cutting, and it's basically a water filled chamber containing the gills and the anise. And you can you see that little mantle cavity right there. Now we're gonna talk about a bunch of different classes of mollusc and the first one not a ton to say about these guys air called kittens. They totally look like some type of prehistoric organism. And what defines them is that they have a shell, which you can see on the top right here. This is the shelves, and the shell is made up of eight dorsal plates. You can see there's like eight segments to this shell. You can also kind of see the foot poking out from underneath this chitin. Now gastro pods, probably an organism. You're much more familiar familiar with these are slugs and snails. They're gonna live both in, uh, marine and terrestrial environments. And while many of them have shells, not all do. Of course, are snail pictured right here has a shell. Um, but, you know, there's plenty of these organisms thes gastro pods that don't have shells. Now, many of these species actually reproduce through sexual reproduction. If you ever want to see, like a wild YouTube video, look up like slug reproduction something like that pretty crazy acrobatic act, acrobatic act. Some species, however, perform parthenogenesis, which is that type of a sexual reproduction we discussed previously. With that, let's turn the page.

bivalves are arguably the most delicious molluscs. Though I think it's up for debate with cephalopods. Now, all species of bivalves are aquatic and contain their body within two shells. And these air organisms like clams, mussels, oysters which you can see right here. And a very important feature of oyster anatomy is lemon and, of course, uh, inside here Menuet sauce. Very important for oysters. Of course, I'm kidding here. However, when you look at that sort of meaty body inside the shell, what you're looking at is both of foot and the visceral mass. And the shell itself is kind of acting as the mantle here. So, you know, looks different from the picture we saw in the previous page when we discussed the an enemy. But all those parts are still here now. Uh, most bivalves are suspension feeders, and they lack that radel a that rasp like eating apparatus. Instead, they, you know, move water through their bodies and pick up on little particles of food that air suspended in the water. And they trap this food in their gills and you can see thes tubes coming out of these clams over here. And those are the structures that they're using to feed now. Cephalopods, as I said, kind of also in the running for most delicious mollusc really hard to say. Yeah, really, really difficulty. It's such a toss up. I mean, calamari here really important cephalopod. I don't know what we do without squid. Most cephalopods are marine predators that have, ah, foot that basically evolved into tentacles. That's what I was referring to earlier when I said, you know, see an example of the foot taking really interesting morphology. Well, its tentacles on these cephalopods And these are, um you know, organisms like squid like this Nautilus here and these guys move in a really cool way. They use the structure called Siphon, which is this muscular tube right there to eject water. And this actually allows them to travel through what is technically jet propulsion, Believe it or not. So thes Air Nature's jets, Basically now, uh, there the Onley molluscs to have a closed circulatory system and cephalopods in general are pretty advanced organisms. They actually have a sophisticated nervous systems and pretty complex brains. They also have some pretty cool sensory organs and, ah, a variety of other adaptations. You know great example are cuttlefish, which are able Thio camouflage themselves. They have, you know, very sophisticated nervous system. There's also some pretty famous and funny examples of occupy tricking researchers, studying them, proving that these animals actually have some pretty sophisticated cognition. Now, unfortunately, the last type of creature I want to discuss is kind of yucky and is not a mollusc. That's pretty important to note. Analysts are not a type of mollusc their their own Phila and, uh, they're culminates. Most are segmented worms and they both live in aquatic environments and in damp soil. And we're gonna see too sort of basic kinds of analysts to these poly Keita which have para podia and you can see all these little para podia here these little you know, leg like structures along the worm body coming out of, uh, the segments of the worm. And these para podia have what are called key tie, which are basically these kindness bristles that the worms used to propel themselves through the water. And if you look, you can see there's sort of these like light projections sticking out of the tips of the para podia. Those are the key to those air. The bristles that the worm uses Thio, you know, almost swim. You could think of it as so the other type of worm is going to be stuff that you probably a little more familiar with these organisms, like earthworms and leeches. They're they're called clit, a lotta. And these organisms are hermaphrodites, meaning they can reproduce sexually. Um, and Uhh. The organism has both the male and the female parts, although some species will actually reproduce a sexually. That's the end of this video. I'll see you guys.