Definition of
Parasite
From Latin parasitus (although with more remote origin in a Greek word that means “diner”), a parasite is an organism that lives at the expense of another species. The parasite, which can be animal or vegetable, feeds on the other organism, weakening it, but generally without killing it.
The biological interaction involving parasites is known as parasitism. The species that hosts the parasite is known as Guest or host and suffers a deterioration of its reproductive capacity due to the action of the other organism that, in turn, manages to improve its own conditions and its capacity for survival.
- How does a parasite work?
- Some examples
- Parasite in colloquial language
How does a parasite work?
It can be said, therefore, that the parasites benefit from the association they establish with the other organism, while the latter is harmed by the type of interaction.
In some cases, the parasites themselves can become hosts for a third species, which is known as hyperparasite. In this way a chain is produced where the hyperparasite lives at the expense of the parasite, and the parasite does the same with its Guest.
With the passage of time and successive generations, the host organisms manage to develop certain defense mechanisms that drive away the parasites or minimize their field of action. Parasites, however, can achieve physiological and morphological transformations through natural selection.
It is worth mentioning that symbiotic relationships between a parasite and its host can be beneficial for the life and evolution of the latter, although this is the minority of cases.
It can help you: Evolution
Some examples
The action of some of the parasites that most commonly attack our species is detailed below:
* hookworms: they are worms that begin their life cycle outside our body and reach it through fruit, vegetables or contaminated water. Once in the intestine, they stick to its wall and feed on blood to grow, which can cause a kind of anemia known as hookworm. Among the symptoms caused by the presence of these parasites are diarrhea, nausea, loss of strength and pain in the abdomen;
* flatworm flukes: find their habitat in the bloodstream of their hosts and are the cause of schistosomiasis (a disease that causes high fevers and hives, among other symptoms, and can cause death). Before entering another organism, they live in water. Their presence is manifested through damage and inflammation in some organs, mainly the liver, and they can stay in the same body for several decades, sometimes without showing symptoms for a long time. When they do, these are usually cough, various aches, lethargy, and fever;
* wuchereria bancrofti: are carried by mosquitoes and released into the blood of the host. Their larvae make their way to the lymph nodes, especially the genitals and lower extremities, and reach adulthood within twelve months. They usually cause a disease of the group known as filariasisespecially the elephantiasis (causes excessive growth of certain parts of the body). Among the symptoms that are noticed in its presence are chills, pain in the lymph nodes, fever and skin infections;
* entamoeba histolytica: is a single-celled organism that attacks people and other primates. It is found in fruits, moist soils and in water. Fecal contamination contributes to its spread. It is worth mentioning that the death rate attributed to it exceeds that of the rest of the protozoa. Diarrhea, weakness, weight loss and liver abscess are some of the symptoms of its passage through our body.
See also: Lymph
Parasite in colloquial language
Finally, the person who lives, or tries to live, at the expense of another subject, taking advantage of their material resources, is classified as a parasite.
For example: “Maximilian is a parasite; Since he has never earned his own money, he would be sleeping on the street if it weren’t for his parents.”.
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