Obligate Parasites: Facultative And Intracellular

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Obligate Parasites: Facultative And Intracellular
Obligate Parasites: Facultative And Intracellular

Video: Obligate Parasites: Facultative And Intracellular

Отличия серверных жестких дисков от десктопных
Video: Obligate parasite, Facultative parasite, Obligate saprophyte, Facultative saprophyte,Haustoria #PPP6 2023, February
  • 1 Characteristics of parasitic organisms
  • 2 Features of the life cycle
  • 3 Main types

    • 3.1 Scabies mite
    • 3.2 Human Ascaris
    • 3.3 Demodex
    • 3.4 Pork chain
    • 3.5 Baby pinworm
  • 4 Intracellular live individuals

The concept of parasitism includes the interaction of organisms, where the vital activity of one is completely dependent on the other. For example, tissue parasitism often occurs, which can lead to poor health or death. Of the popular worms, obligate parasites are considered the most common. Their life cycle is not possible without the presence of a carrier; outside of another organism, worms simply die. In this article, we will look at what obligate parasites are.

Characteristics of parasitic organisms

obligate parasite
obligate parasite

The type of parasitism directly depends on the specific belonging to the species of worms. The difference is what kind of connection takes place with the host's organism. The main types include the following:

  • Organisms of a random species are obligate parasites that can live both in one organism and parasitize in several. Most of them are able to exist autonomously from each other;
  • Obligate parasitic organisms - such worms are completely dependent on the entire life cycle of their host, their death occurs during a long stay in the environment;
  • Facultative parasites - do not completely depend on the entire organism of their host, parasitize at the initial stage, spend the rest of their lives on their own.

Obligate parasites and their examples include several groups:

  • bacteria;
  • various viruses;
  • absolutely all types of worms.

The main place of their location is body cavities and tissues, skin, human cells.

Life cycle features

life cycle features
life cycle features

The main difference between obligate and facultative parasitism is the level of dependence of the worm on the organism and the life cycle of its host. It has been proven that the obligate species of worms dies outside the body of its host, because it is not adapted to develop in the environment. Typically, these organisms have two carriers:

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  • the main one - there is already an individual in his body that has reached puberty;
  • intermediate - its process includes larval development.

As a rule, obligate parasitism has different localizations:

  • worms - living in the body cavity or endoparasites;
  • ticks, lice - living on the surface of the body or ectoparasites;
  • chlamydia and viruses - intracellular parasites.

It should be understood that these worms have a sufficiently developed reproductive system and are capable of laying millions of eggs every day. Their nervous system is primitive, and their sense organs are practically reduced.

Main types

Parasitic organisms are divided into several types that can harm the body and cause significant discomfort to humans. Each of the types of worms manifests itself in different ways, there are some that do not immediately manifest themselves in symptoms. Let's consider in more detail about obligate living individuals.

Scabies mite

scabies mite
scabies mite

It is legalized on the skin, gets in due to the penetration of an adult tick. You can trace it by its moves, which are visually noticeable. As a rule, they live in non-rough areas of the epidermis: the wrist, the bend of the elbows, between the fingers, the armpits.

Human roundworm

A parasitic round worm capable of infecting any system and organ at all stages of its development. The larvae disrupt the transport function of erythrocytes, thereby causing anemia.


parasitizes the mucous membrane of the eye
parasitizes the mucous membrane of the eye

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Infection occurs when worm eggs hit, as well as through close contact with an already infected person. As a rule, it parasitizes on the mucous membrane of the eye and the hair follicle. It feeds on the secret of the epidermis.

Pork chain

Infection occurs when eggs from fecal matter enter the digestive tract of the intermediate carrier. With the help of the bloodstream, it is carried throughout the body and settles in the muscles, where it develops into larvae and takes the form of small bubbles. A person can become infected with pork tapeworm when eating foods that have undergone poor heat treatment.

Baby pinworm

baby pinworm
baby pinworm

This worm lives in the human body, it is classified as a round species. The life cycle goes through all stages of development within all human systems, while the parasite can stay in the body for a long time during re-infection. Pinworms are considered the safest for health and the body as a whole for humans. However, with an advanced stage of pathology, they can cause serious complications.

Intracellular living individuals

When representatives of intracellular parasites come into contact with a person or animal, various diseases can occur. The main varieties include the following types:

  • Chlamydiae are small individuals that use the nutrients of their host and have a cell membrane. This parasite is capable of causing asthma, bronchitis, respiratory failure, pneumonia, prostatitis;
  • Rickettsia is a gram-negative parasite that is similar to bacteria and viruses. It is able to stay inside the body for up to 10 years, manifests itself under favorable conditions. When it enters the human body, it completely affects all organs, a rash appears on the skin, and the pathology itself proceeds in an acute form;

Viruses are simple in structure, multiply inside the cell, as a rule, parasitize in the cells of animals, plants and unicellular microorganisms

Of the optional parasites, an amoeba can be noted, which, when ingested, is able to take root and begin to reproduce, as a result, a change occurs in the functionality of organs, and death occurs.

Regardless of which parasites are facultative and obligate, have struck a person, it is recommended to contact an infectious disease specialist. Only a clinical study of living organisms is capable of eliminating this pathology and relieving a person of discomfort.


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