by Jason Amores Sumpter
Was this helpful ?
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.