The parasite has a life cycle: stages of development

Parasitism is called form a relationship in which one organism (the parasite) uses the other (home) power as a source of temporary or permanent habitat. The owner applied some damage, while the parasite depends on its stages of development. The set of all stages is called a lifecycle.

stages of the parasite

Forms of parasitism

Forms of existence of the parasites varied. It is true, the wrong shape, as well as discretionary and obligate parasitism. Alaistaito is mainly engaged in the study of the phenomenon of true parasitism.

About parasites, when injected into the host organism, the carrier interferes with his life, but the cycle of their effect is short-lived. Examples of forms: leech in the nasopharynx and nasal cavity of the individual. This form can cause the death of the carrier, because the blockage of the airway.

The classification of the forms included:

  1. Obligate parasitism. Most in this group. All the life cycle of the micro-organism associated with a person, he does not live outside the body, or may increase. Examples: Rickettsia and chlamydia
  2. Optional parasitism. In this case, the micro-organisms can lead to a free life, but let the human body to perform part of its development life cycle. Examples of this are species of synanthropic flies. Their larvae develop only products, but once in the human gut, becoming the cause of intestinal myie its.

Distinguish between parasitism at the time of contact. Temporary parasites to use host-only food. Example: blood-sucking arthropods.

Permanent parasites are divided into the following types:

  1. In place. They perform all development stages inside the host or not. It is lice, species of Trichinella spiral, itching mites, and others.
  2. The amount of time. Life cycle they spend or parasitic condition, or for free. An example is the eel intestinal.

How is a cyclic stage

How is the life cycle of the parasite? The functions of the following stages of development:

  • function solution;
  • the phase of active growth.
  • the dream task is to get the different environment;
  • the function of asexual reproduction.

The owner is called intermediate if it is populated by the larvae of the parasite or they perform the function of asexual reproduction. In this case, it is the source of infection, permanent owners. The second value of the intermediate cycle includes the stages of solution. Sometimes an intermediate carrier to provide the need, development and survival, as disappearance at the time of the final owners.

When the developmental cycle of the micro-organism to changes two or three intermediate hosts, the first is called the interval of 1, the second is optional.

The final host is a cycle of development and reproduction sexually Mature stage of the micro-organism. The final carrier of the parasite goes through an intermediate, or a direct connection.

Reservoir parasitism can penetrate into the organism of the definitive host. The reservoir, the pathogen can remain for a long time, to build and transfer to the surrounding areas.

Conqueror-master allows to feed external parasites. Because they eat parasites? They get there just power. For example, bugs that eat human blood. Another example is the mites.

The life cycle of parasitic micro-organisms can be divided into two large groups:

  • Simple;
  • Complex.

Simple group cycles occur without change. Such organisms are Entamoeba histolytica, Ascaris, whipworm and others.

Difficult group contains several intermediates. It can be a vertebrate, they are a parasitic organism goes through several stages of development, or reproduction. Examples: helminth eggs are transported by flies to food or cockroaches.

Part parasitic organisms is low specificity. They meet wild animals, Pets, but can live with a man. Such representatives are wolfarth fly, liver fluke, and tapeworm. Cause of human infection in these examples comes from animals. Diseases caused by these pathogens are called zoonotic.

parasites in the body

How are parasitic organisms carrier? Agents who have settled in the digestive tract, secrete eggs or larvae in the faeces. Information about the methods of breeding to help identify an accurate diagnosis, pathogen.

If you compare a species to live in freedom and parasites, the life cycle of the latter is much more difficult. Free type easily cope with the problems of reproduction and resettlement, and parasitic organisms evolving complex steps. They have a lot of larvae-cycle, the current housing in the different environments, performing different functions. These are the functions of settlement, rapid growth, passive waiting, reproduction.