Flatworms are endoparasites and live inside other animals. They feed on substances that come from the food of the host animal. The intestines are absent in flatworms. They belong to hermaphrodites. Propagation method: bisection or egg laying. The body shape is long and flat. They do not have a circulatory system, and their length can be from 1 mm to 30 meters.
Liver fluke
Flat worm leading a parasitic lifestyle. Lives in the ducts of the liver of cattle, as well as in humans. It has a strongly flattened trunk of a leaf-shaped shape from three to four centimeters long, devoid of cilia. The mouth, the edges of which are thickened, forming a muscular suction cup, is located on the front end of the body. On the abdominal part there is another suction cup. Thanks to them, the worm attaches to the host liver. The parasite is fed with blood and liver cells, which it sucks in with the help of the oral sucker. The hepatic trematode has no intestines.
The parasite is a hermaphrodite. After fertilization, the eggs enter the intestines of the host, and then with the feces of the animal or person are excreted. The egg receives further development by falling into the water. Microscopic hatched larvae covered with cilia penetrate the bodies of snails, grow and multiply. Newly appeared larvae with a swimming tail, but without cilia, are released from the body of snails and fall into the water. There they attach themselves to plants, discarding the tail and forming a dense shell called a cyst around them. During a watering hole, animals swallow a cyst, and a parasite develops from it, which has no intestines. The hepatic trematode begins a new development process. A person is also able to become infected through water.
Wide ribbon
This is a large parasite up to 10 meters long, which lives in the intestines of humans and some predators. The body of a wide ribbon consists of the following parts:
- head. It has an oval shape and very small dimensions, up to 5 mm in length;
- neck. Connects the head with the torso;
- proglottids. Wide segments of the body of the worm. They may contain several thousand.
At the narrowed front end of the body, the head has two slits, with the help of which it pinches the host tissue and remains in the small intestine. In the middle and back of the chain are mature segments, in the center of which there is a uterus filled with eggs. Through the uterine opening, the eggs enter the intestine and are excreted with feces. For the development of lentetsu, two hosts are needed:
copepods and fish of various species. You can become infected by eating poorly processed fish. The wide ribbon has no intestines, and it draws out nutrients from the human and animal body. As a result, acute vitamin deficiency occurs, especially vitamin B12.
Pinworms
The intestines are absent in pinworms, which enter the human and animal body through the oral cavity, penetrate the intestine and begin to multiply. These are white worms, the length of which can reach 10 mm. The rear end of the body is sharp in females, and in males rounded. Pinworms are attached to the walls of the intestine by the mouth, where there is a slight swelling. Helminth eggs are colorless, oval. The entire path of development in parasites passes in the human body.
Pinworms have no intestines, so they feed on blood and drain nutrients from the human body. They live in different parts of the intestine, and mate in the ileum. After mating, the males die, and the females are filled with eggs. The female lays them near the anus up to 15,000 pieces, then dies. After several hours, larvae emerge from the eggs. Pinworms have a life span of about a month. As a result of their life activity, intoxication occurs in humans, which leads to damage to the nervous system and liver.
Roundworm
This is a round spindle-shaped worm with a pinkish tinge, lives in the human body. Gets there with dirty vegetables and fruits. The intestines are absent in males and females, which differ in body length. Males grow up to 25 cm in length, and females grow up to 40 cm. At one time, a female individual can lay up to 24,000 eggs.
The small intestine is the favorite place for roundworms to live. From it, she can easily crawl out to lay eggs. These helminths, unlike others, do not stick to the walls of those organs in which they live. Ascaris has no intestines, and it can live in different internal organs, eating at the expense of the human body. The life span of roundworms is one year, then they die.
Bull tapeworm
The intestines are absent in the tape flat helminth, which affects the human body. Cattle are an intermediate host for bovine tapeworm. In the human body, tapeworm reaches a length of up to 12 m, his body consists of three parts:
- scolex. Located in front of the worm, has four suction cups for attachment to the walls of the intestine;
- neck;
- strobe. Consists of chains of proglottids that are filled with thousands of eggs. They grow from the neck and push ripened towards the end of the body. Then they come off, and thousands of larvae enter the human body.
In bovine tapeworm there is no intestine, it eats at the expense of man, sucking carbohydrates. In the human body can parasitize up to 25 years. And it gets there with meat products, during the preparation of which the temperature regime was not observed.
Interesting Facts
- Worms are very diverse in size. Some species can only be seen under a microscope, while others are longer than 10 m.
- Worms can live in the lungs, liver, brain, skin, and even the eyes and muscles of an individual.
- One female roundworm can lay 250,000 eggs per day. The size of roundworm can be up to 50 cm.
- Worms feed on blood. They can suck up to 400 ml per day.
Conclusion
Which worms have no intestines, you now know. Man, not of his own free will, can become the master and place for the living of worms. These are the lower worms living in the body of an animal or human, which use it to feed and continue the life cycle. For example, the intestines are absent in the hepatic trematode, wide ribbon, bull’s tapeworm, pinworms, roundworm, so they all parasitize in the body of a person or animal.