Flatworms - The Secretion System Of Flatworms

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Flatworms - The Secretion System Of Flatworms
Flatworms - The Secretion System Of Flatworms

Video: Flatworms - The Secretion System Of Flatworms

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Video: Flatworms 2023, February

Last updated 1 March 2020 at 01:20

Reading time: 5 min

The group of flatworms is a class of protozoan invertebrates. In total, there are about 13 thousand species of worms.

Therefore, it is impossible to start the disease in any way, in some cases nematodes lead to the death of the owner. Invasions live in fresh water bodies, salt water, most love soil, grass, moss.

Bilateral symmetry is determined by the right half and the left, there is a ventral and dorsal side. The head and tail regions are well defined. Muscle fibers are located under the cover of the body.

The first side consists of a part of cells of a loose consistency, called parenchyma. It contains all the internal organs of the worms. The respiratory organ in flatworms is absent, some do not need air at all.

The group identifies 7 types of names:

  • ciliary;
  • monogeneans;
  • cestoid;
  • tape;
  • trematodes;
  • digenetic flukes;
  • gyrocotilides;
  • aspidogastra.


  • 1 General characteristics
  • 2 Overview of ciliary parasites
  • 3 Tape invasions
  • 4 Monogenea
  • 5 How can you get sick?
  • 6 Symptoms

    6.1 Similar articles

general characteristics


The worm got its name from the tape form, which is flattened. The body is a solid muscle, covered with a single layer of epithelium. The muscle layer is transverse. Constant contractions of the woven bundles provide worm-like movements, contractions.

Nematodes are often hermaphrodites, meaning that reproduction occurs without the presence of the opposite sex. The reproductive system of flatworms consists of seminiferous tubules and ovaries. Some microorganisms have a digestive system that includes the intestines.

The anal openings and circulatory system may be missing. The intestine consists of the cecum, the swallowing of food begins from the mouth section, where it goes to the middle section and is digested. The undigested amount of food is thrown back into the oral cavity.

In small classes, the stomach forms one straight line, in large ones it branches. Some large creatures include anal pores, but these are rare. Since the message does not have an airway, this means that most microbes coexist perfectly well without oxygen.

The nervous system is called diffuse, represented by the head node and the trunks extending from it, stretching along the entire body.

The places of accumulation of nerve endings are provided by contractile movements. The free-living population contains the eyes, the olfactory and tactile center, the balance, which are located in the head compartment.

As mentioned earlier in the article, the internal organs are not separated from each other by anything, only a connecting tissue. The parenchyma protects against harmful factors, performs supporting functions and the work of metabolism, accumulates useful substances in reserve. Hence, the worms are called parenchymal or noncavitary.

In parasites, excretion occurs with protonephridia. They are engaged in the removal of dissimilation of products, the decaying components fall into the intercellular space. From where they chase ciliated cells, bundles of cilia. Excretory tubules come from the cells.

Overview of ciliary parasites


Ciliates cover 2000 thousand nematodes. Turbellaria live all over the world, most in water, where they first originated. Predators by nature, eat small microorganisms, insects, protozoa. There are non-intestinal representatives and individuals with a straight abdominal cavity. Representative of ciliary planaria.

In length, the animal is about 10 millimeters, tape-shaped. The body is covered with cilia. The walls of the body are composed of skin and muscles. Muscle fibers make up 3 layers oblique, longitudinal and annular, due to this, microbes easily move and change.

The parenchyma is located in the cavity of the sac between the organs. The mouth opening is located on the abdomen or in the middle of the body, also in the tail. Subtypes of ciliates that do not have an intestinal tract digest food by phagocytic cells. In others, nutrients are absorbed through the mouth, the remains are thrown there. Excretory appointment is carried out by protonephridia.

Nerve impulses are at the beginning end. Paired brain node with trunks, of which the largest lateral ones contain nerve cells and branches. The diametric ones are fastened with circular jumpers, because of this, a kind of mesh is formed.

Tape invasions


This includes 4000 thousand pathogens. It is classified as a parasitic form that lives in the stomach of humans or mammals.

It feeds and reproduces at the expense of the host. In the external environment, eggs and larvae are preserved. Vital activity is 45 days, then death occurs. A special membrane protects the embryos from the harmful effects. Thanks to her, embryos are not afraid of cold, heat, moisture, radiation and chemical effects. The life cycle is primitive.

Once in the body, the tape takes off the membrane and rushes into the abdominal cavity, the process of transformation into adults takes 7 days. The larvae migrate through the lungs, blood vessels, and blood. Having reached puberty, they reproduce. The outlet is carried out by emptying.

Digestion is well developed due to the main work of sucking out nutrients. The body of a biohelminth is from 1 mm to 15 meters. It starts from the head, goes into the neck and ends with the anal passage. There are hooks on the initial area, with the help of which the protozoa are fixed on the mucous surface.

No different from other types. Nematodes have annular and longitudinal muscles with dorsoventral bundles. The nervous and olfactory centers are poorly formed. The main job of tapeworms is to reproduce offspring. Therefore, they are endowed with both male and female functions at once. The female is capable of producing up to 200 thousand eggs per day.

They can get into the lungs, pancreas, heart. The advanced stages lead to serious complications, cure becomes difficult.



Monogamous flukes are ranked among the genus of tape. They have an elongated, rarely rounded shape. A disc is fixed at the end. The haptor serves as a tool for attachment by hooks or clamps, muscle suction cups. The parasites are not more than 1 mm long, colorless, so you can see the insides of the worm. Cavity-free class, cavities are filled with soft connective tissues.

Parasitize at the expense of others. The mouth and powerful muscles are actively developed. There is no circulatory system or respiration. The processed products are allocated through 2 holes located on the sides. By gender, there may be a role for women and men.

The genus of trematodes, cystodes, apidogastras, gyrocotylids and are exotrophic animals. They have no sense organs, and the nervous system is poorly formed. The last two live in molluscs and fish.

How can you get sick?


You can find out about flatworms that have invaded the body by looking at numerous symptoms. The disease caused by helminths is called helminthiasis.

The main ways of infection are:

  1. drinking and bathing from contaminated sources;
  2. contact with an infected person;
  3. poor handling of fruits and vegetables;
  4. dirty hands.

In order to prevent the appearance of uninvited guests, you need to wash your hands properly before each meal, do not drink raw water from the tap. Monitor the child's hand hygiene, especially after going outside and playing with pets. Rinse fruits and vegetables well under running water. Properly heat treatment of meat and fish.



The fact that invasions have started in the body can be found out by some factors. In some, they are pronounced due to the development of microbes in large numbers, in others, the presence is almost imperceptible. The process of excretion of substances leads to intoxication.

Classic signals will be:

  • allergic rashes on the body;
  • diarrhea and nausea;
  • headaches;
  • high temperature in the acute phase;
  • loss of appetite.

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