Flatworm
The flatworms, flat worms, Platyhelminthes, Plathelminthes, or platyhelminths are a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrates. Unlike other bilaterians, they are acoelomates, and have no specialized circulatory and respiratory organs, which restrict…
What are the characteristics of phylum?
i) They are unicellular, diploid, colonial or free living. One group of them (Pennales) live in fresh water and other group (Centrales) live in saline water of sea ii) They are non-flagellated. but the gametes are motile iv) Cell wall is enriched with silica and is well tined with salve (theca).
What are the unique features of Platyhelminthes?
What are the unique features of platyhelminthes?
- Their body is dorsoventrally flattened.
- They exhibit bilateral symmetry.
- Also, they are triploblastic, with three germ layers.
- They do not have a body cavity and are acoelomate.
- Body is soft and unsegmented.
- They are mostly parasitic with a few free-living.
What are three characteristics of the phylum Chordata?
Phylum Chordata
- Characteristics Of Phylum Chordata. It is a longitudinal, cartilaginous rod running between the nerve cord and the digestive tract. ...
- Classification Of Phylum Chordata. Vertebrata (vertebrates). ...
- Examples of Phylum Chordata. This chordate belongs to the sub-phylum Vertebrata. ...
What phylum has a true coelom?
Type of Coelom: Animals in phylum mollusca are coelomates. Type of Body Plan: Species in phylum mollusca are protostome, meaning their mouth develops bebore their anus. The species within phylum mollusca contains some form of all organ systems. Specialized Cells/organs: Some species have radula which are part of the digestive system.
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Which of the following is characteristic of the phylum Platyhelminthes quizlet?
Which of the following is characteristic of the phylum Platyhelminthes? They are dorsoventrally flattened. This is why they are also called flatworms.
What are the 3 classes of phylum Platyhelminthes?
The Phylum: Platyhelminthes includes the flatworms (Planaria, flukes & tapeworms) Three Classes treated here are Turbellaria, Trematoda and Cestoda.
What is the description of phylum Platyhelminthes?
flatworm, also called platyhelminth, any of the phylum Platyhelminthes, a group of soft-bodied, usually much flattened invertebrates. A number of flatworm species are free-living, but about 80 percent of all flatworms are parasitic—i.e., living on or in another organism and securing nourishment from it.
Which one of the following is an example of phylum Platyhelminthes?
Schistosoma is a parasitic flatworm belonging to phylum Platyhelminthes.
What are 5 characteristics of phylum Platyhelminthes?
Characteristic features of Phylum PlatyhelminthesTheir body is dorsoventrally flattened.They exhibit bilateral symmetry.Also, they are triploblastic, with three germ layers.They do not have a body cavity and are acoelomate.The body is soft and unsegmented.They are mostly parasitic with a few free-living.More items...
Which of the following is not true about Platyhelminthes?
Answer: option d is the correct answer because only planaria possess high generation capacity and fasciola does not possess high generation capacity.
What do all Platyhelminthes have in common?
Phylum Platyhelminthes All have the following characteristics: bilateral symmetry, organs embedded in a solid cellular matrix (the parenchyma), a sac-like gut without an anus, a nervous system with an anterior “brain” and lateral nerve chords, and internal fluids that are regulated by protonephridia.
Which of the following is are belongs to Platyhelminthes group?
Trematoda is a class within the phylum Platyhelminthes.
What is the structure of Platyhelminthes?
Platyhelminthes lacks exo- or endoskeleton and as such the body is soft. The epidermis is single-layered and in some cases it is syncytial. The epidermis may be ciliated in whole or in part. The sub-epidermal layer consists of musculature of circular, longitudinal and oblique fibres.
Which of the following does not belong to phylum Platyhelminthes?
Option A: Roundworm body looks hard so it does not come under the phylum platyhelminthes. It also has a body cavity. It has a complete digestive system and a simple nervous system. So it is the correct answer because characteristics aren't related to phylum.
What are characteristics of phylum?
The phylum has the following distinguishing characteristics:These are pore-bearing multicellular animals.The body has no organs.They exhibit holozoic nutrition.The body is radially symmetrical.They can regenerate their lost parts.
In phylum Platyhelminthes, the excretory organs are?
A flame cell is a specialized excretory cell found in flatworms (except the turbellarian order Acoela), rotifers and nemerteans. Flame cells functi...
Members of phylum platyhelminthes are generally called as?
Platyhelminthes very commonly known as flatworms or tapeworms, these animals are soft-bodied invertebrate animals. There are around 20,000 species...
Mention the unique features of phylum platyhelminthes.
The unique features of the phylum Platyhelminthes are as follows: They have a dorso-ventrally flattened body The body is covered with the ciliated...
Mode of nutrition in platyhelminthes is?
Phylum Platyhelminthes includes triploblastic, acoelomate, bilaterally symmetrical and dorsoventrally compressed flatworms. Phylum Platyhelminthes...
What are the unique features of the phylum platyhelminthes?
Answers : The unique features of the phylum Platyhelminthes are as follows: They have a dorso-ventrally flattened body. The body is covered with the ciliated epithelium. These are acoelomate. They have a sac-like digestive cavity.
What is the phylum of Platyhelminthes?
Phylum Platyhelminthes. (Source: Wikipedia) Platyhelminthes are common ly known as flatworms or tapeworms. They are a group of soft-bodied invertebrate animals. As a matter of fact, there are around 20,000 species of these animals. A few of these live as parasites on humans and other animals. Furthermore, it is because of this parasitic nature ...
What is a flame cell?
Answer: A flame cell is a specialized excretory cell found in flatworms (except the turbellarian order Acoela), rotifers and nemerteans. Flame cells function like a kidney, removing waste materials.#N#The nephridium is an invertebrate organ that occurs in pairs and performs a function similar to the vertebrate kidney. Nephridia remove metabolic wastes from an animal’s body.#N#The malpighian tubule is a tubular excretory organ, numbers of which open into the gut in insects and some other arthropods.#N#Green glands are excretory organs in Crustaceans.
What percent of flatworms are parasitic?
Around eighty percent of the flatworms are parasitic in nature, while a few free-form flatworms are also present. The free-living forms are scavengers or predators. The parasitic species feed on the tissues of the host organism in which they live. The animals in this phylum have a diverse range in size.
How many species of Platyhelminthes are there?
Answers: Platyhelminthes very commonly known as flatworms or tapeworms, these animals are soft-bodied invertebrate animals. There are around 20,000 species of these animals. A few of these live as parasites on humans and other animals.
What is the most distinguishing feature of flatworms?
The most distinguishing feature of these invertebrates is their flat body. As the body does not have any cavity, they are flat. The body is also not segmented and they do not have specialized systems. Around eighty percent of the flatworms are parasitic in nature, while a few free-form flatworms are also present.
Can parasites live in hostile environments?
And so, can survive in hostile environments. Furthermore, these worms belong to Phylum Platyhelminthes.
What kingdom is Platyhelminthes in?
Phylum Platyhelminthes belongs to the kingdom Animalia. This phylum includes 13,000 species. The organisms are also known as flatworms. These are acoelomates and they include many free-living and parasitic life forms. Members of this phylum range in size from a single-celled organism to around 2-3 feet long.
Where do tapeworms live?
It is also known as the pork tapeworm and is found in all the countries where pork is consumed. They live as parasites in the small intestine of human beings and their larva are found in the muscles of the pigs. It is a hermaphrodite and undergoes self-fertilization.
How do worms respire?
They respire by simple diffusion through the body surface. They have an organ system level of organization. They do not have a digestive tract. The space between the body wall and organs is filled with connective tissue parenchyma which helps in transporting the food material.
How do aphids reproduce?
They reproduce sexually by fusion of gametes and asexually by regeneration by fission and regeneration. Fertilization is internal. The life cycle is complicated with one or more larval stages.
Is a squid parasite free living?
They may be free-living or parasites. The body has a soft covering with or without cilia. Their body is dorsoventrally flattened without any segments and appears like a leaf. They are devoid of the anus and circulatory system but has a mouth.
What is the phylum of flatworms?
The representatives of the phylum Platyhelminthes are commonly known as the flatworms or tapeworms. The word ‘Platyhelminthes ’ is derived from the Greek word, ‘platy’ meaning flat and ‘helminth’ meaning worm. They are simple soft-bodied, bilaterian, unsegmented invertebrate animals. The Phylum Platyhelminthes makes up the 4th largest phylum ...
What is the 4th largest phylum in the world?
The Phylum Platyhelminthes makes up the 4th largest phylum among the animal kingdom. But among the acoelomate organisms, the phylum Platyhelminthes constitutes the largest phylum with more than about 20,000 known species throughout the world. Among them, around 80% live as parasitic life on humans and other animals and few are free-living.
What are the four classes of flatworms?
There are four traditional classes of flatworms, the largely free-living turbellarians, the ectoparasitic monogeneans, and the endoparasitic trematodes and cestodes. Trematodes have complex lifecycles involving a molluscan secondary host and a primary host in which sexual reproduction takes place.
How many flatworms live on humans?
Among them, around 80% live as parasitic life on humans and other animals and few are free-living. Flatworms are acoelomate, triploblastic animals. They lack circulatory and respiratory systems, and have a rudimentary excretory system. This digestive system is incomplete in most species.
How many species of tapeworms are there?
The member of the class is commonly known as tapeworms. They contain over 4,000 species which lead endoparasitic life forms. They have long flat and tape-like bodies which can grow up to 18 meters long. They have no digestive, circulatory and respiratory systems.
Where do tapeworms live?
The cestodes, or tapeworms, are also internal parasites, mainly of vertebrates (Figure 3). Tapeworms live in the intestinal tract of the primary host and remain fixed using a sucker on the anterior end, or scolex, of the tapeworm body. The remaining body of the tapeworm is made up of a long series of units called proglottids, each of which may contain an excretory system with flame cells, but contain reproductive structures, both male and female. Tapeworms do not possess a digestive system; instead, they absorb nutrients from the food matter passing them in the host’s intestine.
Where does taenia solium live?
They live as parasites in the small intestine of human beings and their larva are found in the muscles of the pigs. It is a hermaphrodite and undergoes self-fertilization. Taenia solium causes taeniasis where the patient experiences abdominal pain, anaemia, indigestion, restlessness and false appetite.
Definition
Platyhelminthes are the group of organisms having bilaterally symmetrical triploblastic acoelomate body organization containing protonephridia as an excretory system without anus, circulatory and respiratory system.
Identifying characters of Platyhelminthes
Body structure: The body is dorsoventrally flattened and bilaterally symmetrical.
Examples
There are about 20000 living species in this phylum. Some common animals of phylum Platyhelminthes are Planaria, Hoploplana, Polystoma, Fasciola, Geoplana, Anaperus, Taenia, Echinococcus, Paragonium, Convoluta, Schistosoma, etc.
What kingdom is Platyhelminthes in?
Platyhelminthes. Phylum Platyhelminthes belongs to kingdom Animalia. This phylum includes 13,000 species. The organisms are also known as flatworms. These are acoelomates and they include many free-living and parasitic life forms. Members of this phylum range in size from a single-celled organism to around 2-3 feet long.
Where do tapeworms live?
It is also known as the pork tapeworm and is found in all the countries where pork is consumed. They live as parasites in the small intestine of human beings and their larva are found in the muscles of the pigs. It is a hermaphrodite and undergoes self-fertilization.
What diseases are caused by tapeworms?
It is one of the most dangerous diseases in tropical countries. Taeniasis is another disease caused by Tapeworms.
How do worms respire?
They respire by simple diffusion through the body surface. They have an organ level of organization. They do not have a digestive tract. The space between the body wall and organs is filled with connective tissue parenchyma which helps in transporting the food material.
What is the life cycle of a flame cell?
The life cycle is complicated with one or more larval stages. They possess the quality of regeneration. The flame cells help in excretion and osmoregulation. The nervous system comprises the brain and two longitudinal nerve cords arranged in a ladder-like fashion.
Do squid have cilia?
They may be free-living or parasites. The body has a soft covering with or without cilia. Their body is dorsoventrally flattened without any segments and appears like a leaf. They are devoid of the anus and circulatory system but has a mouth. They respire by simple diffusion through the body surface.
History of Phylum Platyhelminthes
What Is The Classification of Phylum Platyhelminthes?
- Based on the mode of life, presence or absence of digestive system, cilia on the body wall, and the classification by Hyman, L.H., \((1951)\), the phylum Platyhelminthes is divided into three classes as follows:
Economic Importance of Phylum Platyhelminthes
- The economic importance of Phylum Platyhelminthes are as follows: i. Flatworms play a significant role in biological communities – marine, freshwater and terrestrial ecosystems. ii. Flatworms absorb all oxygen via diffusion from the surrounding air. iii. Most Turbellarians are carnivorous predators and scavengers and play a role in the food chain. iv. Fasciola causes fasc…
Interesting Miscellaneous Fact!
- Adult tapeworms can measure more than \(80\) feet, i.e.,\(25\) meterslong and can survive as long as \(30\) years in a host. They can also live in human intestines. Fig: Tapeworm Attempt Mock Tests
Summary
- In this article, we studied that Phylum Platyhelminthes are dorsoventrally flat animals having either unsegmented and leaf-like or ribbon-like bodies. They are the first animals to have bilateral symmetry and to undergo cephalisation. These animals have a high level of regeneration, and some are hermaphrodite. Under favourable conditions, they can infect the human body and caus…
Frequently Asked Questions (FAQs) on Phylum Platyhelminthes
- The most frequently raised doubts about Phylum Platyhelminthes are answered here: We hope this detailed article on Phylum Platyhelminthes helps you in your preparation. If you get stuck do let us know in the comments section below and we will get back to you at the earliest.
Characteristics of Platyhelminthes
- Platyhelminthes have the following important characteristics: 1. They are triploblastic, acoelomate, and bilaterally symmetrical. 2. They may be free-living or parasites. 3. The body has a soft covering with or without cilia. 4. Their body is dorsoventrally flattened without any segments and appears like a leaf. 5. They are devoid of the anus and circulatory system but have a mouth. …
Unique Characteristics of Platyhelminthes
- Some of the characteristics that distinguish the organisms belonging to phylum Platyhelminthes from others are: 1. Presence of flame cells. 2. Ladder-like nervous system. 3. Presence of parenchyma in the body cavity. 4. Self-fertilization
Classification of Platyhelminthes
- There are four groups that are Turbellaria, Trematoda, Monogenea, and Cestoda. This was artificial but in 1985, Ehlers proposed aphylogenetically more correct classification, where the massively polyphyletic"Turbellaria" was split into a dozen orders, and Trematoda, Monogenea, and Cestoda were joined in the new order Neodermata. Turbellaria 1. These are free-living organism…
Examples of Platyhelminthes
- Some of the examples of phylum Platyhelminthes are: Dugesia (Planaria) These are found in freshwater ponds or slow streams. Their body possesses cilia and has the power of regenerating the lost part. The head bears a pair of eyes and two lateral lobes. Schistosoma It is found in the mesenteric blood vessels and hepatic portal system of humans and is therefore known as bloo…
Conclusion
- This is all about Platyhelminthes and their different characteristics. Understand the features of the different groups falling under this classification with examples to grab hold of this concept of biology perfectly.