Ciliary Worms (turbellaria): Characteristics And Description Of The Class, Diagnosis And Treatment Methods, Reviews Of Doctors

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Ciliary Worms (turbellaria): Characteristics And Description Of The Class, Diagnosis And Treatment Methods, Reviews Of Doctors
Ciliary Worms (turbellaria): Characteristics And Description Of The Class, Diagnosis And Treatment Methods, Reviews Of Doctors
Video: Ciliary Worms (turbellaria): Characteristics And Description Of The Class, Diagnosis And Treatment Methods, Reviews Of Doctors
Video: Phylum Platyhelminthes Notes 2015 2023, February
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Last updated 10 December 2018 at 17:28

Reading time: 4 minutes

There are a large number of representatives of the world of protozoan microorganisms. These include ciliary worms, of which there are about 3,500 types in nature.

Some of the striped worms are completely harmless, while others can be dangerous to human life and health. Their size depends on the place of the environment where they live.

To see some of them, you need a microscope, and there are individuals that reach 40 cm in length. They can live freely in the environment, but they are predatory.

Moistened soil is also suitable for them. Planaria are considered a distinctive class, as they have a wide variety of colors.

Content

  • 1 The structure of ciliary worms
  • 2 Digestive and excretory system
  • 3 Nervous system and sensory organs
  • 4 Reproductive system and method of reproduction

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The structure of ciliary worms

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These individuals are called cilia for a reason, their entire body is covered with them. The cilia are essential for moving. Ciliated individuals move in space like snakes, they can crawl or swim.

The structure and shape of the ciliary worms are oval, slightly flattened, but there are individuals of an elongated appearance. All representatives of these worms have a bilateral symmetrical structure, in front they have an oral cavity, which is located on the belly.

Flatworms have their own characteristic features of the structure of the ciliary cover, and have ciliated epithelium. There are two types - stuck together and separate cilia. However, not all members of this class possess them.

The worm moves with the help of a secret fluid, which is produced by the secretion glands. Its release occurs in the front of the individual's body, and it helps maintain balance and move freely around the object on which it is located. At the edges of the ciliary glands are of unicellular origin.

The mucus they produce has some toxicity. In nature, they need it to protect against representatives of larger microorganisms. With age, worms begin to lose their cilia, and outwardly it resembles a molt, like a cat or dog.

The internal structure of ciliary individuals completely coincides with the flat type of microorganisms. Their musculocutaneous sac is formed with the help of a muscular organ.

The first is the annular layer, it is located on the outside of the individual.

The second is diagonal, it is at a slight angle, and the last is a longitudinal layer that forms in the lower part of the body.

With the contraction of muscle tissue, the movement process is accelerated, and large ciliary individuals increase the sliding speed.

Digestive and excretory system

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The digestive system of ciliary worms has a complex internal structure, consisting of numerous organs. Through them, the nutrients required for vital activity enter inside.

There are ciliary individuals that do not have a full digestive system, they are called without intestinal. Individuals with a well-formed intestinal tract are divided into two types, these are ramus and rectal.

And in individuals with a rectal type of structure, the mouth is located in the front part, it is adjacent to the pharynx, which has blind branches of the intestinal tract. On the body of worms there are glands that provide external digestion of food, and they are called pharyngeal.

In the process, he secretes a secret that is able to digest food from the outside, and then absorbs it into his body. They feed mainly on small microorganisms that do not have vertebrae, such as crustaceans.

They do not have a very simple excretory system; it consists of a significant number of pores through which processed substances leave the body. The numerous branches that make up the excretory system connect to one or two major canals attached to the intestinal tract.

When it is absent, the accumulation of unnecessary substances occurs on the upper surface of the body in some cells. After a sufficient amount of excreta has accumulated, they themselves eventually detach from the worm.

Nervous system and senses

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Some members of this class have several nerve endings that are located only in the front of the body. And there are flatworms that have a significant number of neurons that connect to the main trunks, there can be up to 8 of them.

Ciliated creatures have a sensory system. On their body there are cilia that do not have mobility. There are representatives of this class who know how to feel balance, since they have statocysts. This organ is vesicles or pits, the difference is the type of individual.

They react to the environment with the help of sensilla, these are immobile cilia that are distributed throughout the body. In the presence of a statist's organ, an orthogon is possible.

The characteristics of the structure of the olfactory organs are very interesting. Due to the developed sense of smell, turbellaria can find food for itself. The predator has special pits on the body, which receive a signal from the environment, and it is transmitted to the brain system.

Despite the fact that there are several eyes on the body near the cerebral ganglia, they do not have vision. Some scientists argue that large flatworms can still distinguish between objects. Studies have shown that they have a lens that helps to see.

Ciliated individuals differ from flat ones in that they can breathe. Flatworms live in an oxygen-free environment, where they reproduce. Ciliates need oxygen, as they live in a different environment. The predator breathes with the help of its body, that is, there are pores on its surface that absorb oxygen.

Reproductive system and reproduction method

The seminal fluid for fertilization passes through special channels and enters the egg. Then it enters the oviduct and forms a cloaca. The propagation of a class is carried out by a cross method.

Individuals alternately fertilize each other, they inject sperm fluid into the opening of the cloaca. The seeds form eggs, which are covered with shells. Then they lay eggs, and subsequently a new individual hatches from them. In appearance, they are like adult worms.

Reproduction of turbularia is somewhat different from other representatives of the class. They hatch from the egg a small larva, which is already growing in the habitat.

A constriction appears on the body, which after a while divides the body into two separate parts. And gradually they acquire all the vital organs.

Ciliated worms are essential for maintaining balance in the invertebrate population. Predators eat them, and thus do not allow them to grow in large numbers.

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