The evolution of parasitic flatworms, including the Platyhelminthes (Neodermata), has been interpreted to refute the common origin of endoparasitism. These flatworms have developed adaptations to transit from different metabolic conditions to those they are exposed to. The parasitic Platyhelminthes (Neodermata) contains three parasitic groups, each with unique morphology and life cycles. The theory predicts parasites can show local adaptation (LA) to at least one host species, achieving greater infection success of sympatric hosts than allopatric. Platyhelminthes exhibit both aerobic and anaerobic metabolism depending on the availability of oxygen in their environment and/or due to differential oxygen.
Free-living flatworms are mostly predators and live in water or shaded, humid terrestrial environments. Parasitic flatworms protect themselves from the host’s digestive liquids by developing teguments or resistant coverings around their bodies. Sensory cells in the head detect changes in the environment, and flatworms have hooks on their mouths to securely attach to their hosts. They have an excretory system with a network of tubules throughout the body that open to the environment and nearby flame cells, whose cilia beat to direct. Under demanding environmental conditions, flatworms produce resistant eggs able to survive desiccation or enter the host’s body.
📹 Want a Whole New Body? Ask This Flatworm How | Deep Look
Planarians are tiny googly-eyed flatworms with an uncanny ability: They can regrow their entire bodies, even a new head. So how …
What adaptations do parasites have to their parasitic mode of life?
Parasites are adapted to maximize their benefits from their hosts without killing them. Tapeworms, for example, have strong suckers and hooks for attachment to the small intestine lining. They have a large surface area for nutrient absorption and have a large reproductive potential. Mutualism between species can also occur, as seen in bees and flowering plants, where bees obtain nectar for food and spread flower pollen, aiding reproduction in plants.
Similarly, cleaner fish, smaller fish, can display mutualism by swimming near larger fish’s gills and eating parasites around their gills. This relationship provides nutrition and protection for smaller cleaner fish, while larger fish remove the parasites.
How do parasites adapt to their environment?
Parasites can adapt to new conditions through species-specific adaptations, such as freeze and desiccation tolerance, phenotypic plasticity, acclimation capacity, and ecological interactions. These adaptations can buffer the negative effects of new conditions, increasing persistence and adaptation opportunities. ScienceDirect uses cookies and copyright © 2024 Elsevier B. V., its licensors, and contributors. All rights reserved, including text and data mining, AI training, and similar technologies.
What adaptations do free-living flatworms have?
Free-living platyhelminths, primarily carnivorous, are adapted for capturing prey and are found in various environments, including coastal marine habitats, freshwater habitats, terrestrial turbellarian species, and caves. Some species are resistant to extreme environmental conditions, such as osmotic changes and temperature differences. Some marine species, such as Coelogynopora biarmata, have been found in freshwater springs. Terrestrial turbellarian species can be found in soil, moist sand, leaf litter, mud, under rocks, and vegetation.
Cave-dwelling species often show loss of eyes and pigment. Some species can survive temperatures of -40 to -50°C, while Macrostomum thermale and Microstomum lineare exhibit remarkable heat tolerance, found in hot springs at 40-47°C. M. lineare can also tolerate temperatures as low as 3°C. Overall, turbellaria species are adaptable to various environments and are largely carnivorous, allowing them to survive in various conditions.
How do flatworms respond to their environment?
Independent-living flatworms have a central nervous system consisting of a ganglion, a mass of nerve cells in the anterior part of the body, and a nerve cord extending from the brain toward the posterior end of the body. Sensory cells in the head detect changes in the environment, with light-responsive cells clustered in two eyespots and water currents, solid objects, and chemicals in two flap-like projections called auricles.
These sensory organs are the first part of the animal to encounter new surroundings. The ganglion receives information from these sensory structures and sends signals to other parts of the body along two strands of nerve cells running toward the tail.
The excretory system removes waste products and excess water from flatworm tissues. This network runs the length of the animal on each side and opens to the outside through small pores in the posterior region of the body. Connected to the tubes are tiny cells that move wastes and water from the tissues into the tubes, which contain flagella that beat back and forth, creating a current of fluid that constantly moves toward the excretory pores, creating a flame bulb structure.
How do flatworms adapt to a parasitic lifestyle?
Parasitic flatworms develop a tegumentary covering to protect themselves from the host’s digestive juices, and secrete anti-enzymes to neutralize the host’s digestive acids produced in their intestine.
What are the five adaptive features of parasite?
Parasites have evolved adaptive features such as adhesive organs or suckers, loss of digestive system, lack of unnecessary sense organs, and high reproductive capacity. They have been tested on various boards such as IIT JEE, NEET, UP Board, Bihar Board, and CBSE. Free textbook solutions for various subjects are available, including KC Sinha Solutions for Maths, Cengage Solutions for Maths, DC Pandey Solutions for Physics, HC Verma Solutions for Physics, Sunil Batra Solutions for Physics, Pradeep Solutions for Physics, and Errorless Solutions for Physics, Chemistry, and Biology. Additionally, free NCERT Solutions are available for various English Medium classes.
What are the four parasitic adaptations in a parasite?
Parasites exhibit a variety of distinctive adaptations, including the loss of sense organs, the presence of suckers, the absence of digestive systems, and a high reproductive capacity.
What are the adaptations evolved by parasites in accordance with their lifestyles?
Parasites have evolved various adaptations, including the loss of unnecessary sense organs, the presence of hook/adhesive organs and suckers, the loss of the digestive system, and high reproductive capacity. In some cases, parasitic species may evolve with their host taxa, leading to a stable relationship that may be commensalism or mutualism. Parasites may evolve to become less harmful to their host, while hosts may evolve to cope with the parasite’s presence, causing harm to the host.
How do flatworms help the environment?
Flatworms are of significant ecological importance, exerting a profound influence on the dynamics of zooplankton populations in aquatic ecosystems. They serve as a primary consumer of protozoans, rotifers, and algae, thereby regulating the trophic structure of these habitats.
📹 Phylum Platyhelminthes Part 4:Tapeworms of Class Cestoda
It’s time to wrap up our assessment of platyhelminths, and we will finish with a group of organisms you may have heard of, the …
Hi Deep Look fans! I produced this episode. Here are the answers to a few questions you have asked. Nelson Hall, a doctoral student at Stanford University who studies planarians provided me with the answers below. Thanks for perusal! -Gabriela 1- What would happen if a planarian were cut lengthwise, rather than from side to side, as we show in the article? It would take a little longer to regenerate, but it would regenerate all the same. 2- How do planarians reproduce? Some reproduce sexually, by mating and laying eggs. Others reproduce asexually, by breaking off a piece of their body from which a new planarian grows. 3- How do planarians die? Hall says they can die from infection or starvation. “If you really want to kill a worm,” he says, “you can dehydrate it, keep it over 30 degrees Celsius, freeze it, or use toxic chemicals. I’m sure you could get creative with how to kill planarians, but cutting (within reason) and aging will not do it.” 4- If you put a planarian in a blender, would each bit regenerate? “Unfortunately, probably not,” Hall says. “A planarian in a blender will just produce very dead worm mush.” 5- What is the smallest amount of planarian that can regenerate? “If the wound can close and if the remaining fragment has at least one stem cell,” says Hall, then it can grow a whole new planarian. 6- Are planarians immortal? If none of the situations described above were to happen, then yes, a planarian could be immortal. For asexual planarians – the ones that reproduce by breaking off a piece of their bodies and growing a new planarian – there’s no evidence that they age, Hall says.
I actually did this experiment when I was a kid (around 6 I think). There were these thin black worms that we saw when it rained, and my mom told me that if I cut one of them into half they’d become 2 separate worms. So naturally, the next time it rained I went to the balcony, caught one and put it in a bowl to cut it into half. It actually worked. When I cut it, the 2 pieces just became 2 different worms.
The coolest story ever: my friend (60 years old man) got his big toe amputated. Two years later his two grew again. It looks a bit weird (the toe nail has hairs sticking out of it) but who cares! His toe regrew! The doctor was really surprised and couldn’t explain it. Still don’t know why it happened, but my friend is happy 🙂
Thanks for turning, what I’ve been reading in biology text books for years, into a real life example ! I was hoping that you would show the procedure where the planarian head is sliced a dozen times and eventually 12 heads grow back : Hydra planarian! ( Though I can understand some people getting upset about it)
Planarian. Sounds like the perfect new Genesis AI starship (maybe that’s what earth is ) scenario. Adam HER-maphrodite split equals Adam and Eve. If they just hadn’t eaten that fermented fruit from the tree, ah but that’s the next worldorder religion to found upon. New calendar too. Can you imagine the expression on Adam’s face when he head the Creator’s next plan to create Eve? You’re looking at a face that says it all. “YOU’RE GONNA DO WHAT?….”
The reason they are able to regenerate completely is because their structures are simpler than humans.Even if humans have the same amount of stem cells as they do we will not be able to completely regenerate like them, though it’ll help regenerate tissues to a certain extent it’ll probably not be able to regenerate a lost limb.(just my opinion)
Mass energy must be conserved. To regenerate ANYTHING you have to feed it, right? It would have to be impossible for a flatworm chunk to regenerate a head or tail if you put it into distilled water with no nutrients, right? Has anybody performed a mass balance on a flatworm: computed food and energy intake and output?
How did they figure to feed it beef liver? I wouldn’t imagine there are a lot of cows on the bottom of a pond, maybe mannatees. But I guess if nematodes like tapeworms eat cows from the inside out, why not other worms. I wonder what exactly these guys eat in the wild. If I had to guess, living at the bottom of a pond, probably algae. They don’t seem suited for hunting cows.
McDonald’s worker: Welcome to your first job at McDonald’s! Planarian: Thanks! It is really nice to work here! One hour later Planarian: WHEW! It sure is hard work… I wish I could do everything all at the same time. Planarian: Wait a minute…at the same time! That’s it! I know exactly what to do! 10 days later McDonald’s worker: Wow you really know what you’re doing, Planarian! Planarian: Well… you could say from that one planarian… All four planarians at once: You get four!
when i saw the word Phylum, I clicked on it right away…brought me right back to 6-7th grade biology with Kings Play Chess On Fancy Glass Stools K- Kingdom P- Phylum C-Class O- Order F- Family G- Genus S- Species that was how the teacher taught us how to remember the top to bottom of the Animal KIngdom
I hate tapeworms, hookworms etc. The most disgusting parasites next to botfly larvae. 🤮 I actually found a tapeworm in my salmon from whole foods. Too bad I was almost done eating my piece when suddenly I pulled out a long flat piece of worm. A little too late to spit my food out. I prayed I cooked it enough to kill the eggs 🫠