Parasitic Symbiosis: Definition, Meaning, Overview, Examples, Types

What Is Symbiosis?

Symbiosis can be classified as the intimate associations, which are usually, and may be permanent, between two different organisms of different kinds and can be of three types, including mutualism, commensalism, and parasitism. This discussion looks at the aspect of parasitic symbiosis by defining it as a relationship between mass quantity and the supply chain where the former draws nutrients and shelter from the host while damaging it.

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Thus, the subject is important since parasitic symbiosis analysis is essential in terms of ecology and medicine. Thus, it affects host species by altering their general well-being, behaviour, and other population attributes that have effects on ecosystems. Knowledge of a parasitic relationship can also help in controlling diseases, the conservation of species, and checking the order in the ecosystem.

What Is Parasitic Symbiosis?

The parasitic symbiosis is described below-

Definition And Characteristics Of Parasitic Symbiosis

Ecological parasitism is one of the relations of mutual interdependence; one of the parties – the parasite – gains some advantage at the cost of the other – the host. This relationship is defined by the fact that a parasite derives its needs such as food, and shelter and at times reproduces from the host. Disease-causing organisms generally pose a threat to their host through discomfort, serious sickness, or death sans instantaneous death in the host, because this removes their food source

Parasite And Host Relationship

This relation is characterized by the parasite using the host either externally or internally for his/her nutrients and even shelter. In this relationship, one organism benefits at the expense of the other, whereby the host offers the environment or the requirements in which the parasite can thrive, at the same time receiving some health repercussions due to the presence of the parasite.

Dependence Of Parasite On Host For Nutrients

Some of the requirements that parasites have are food and this is provided by the hosts. It can cause different evolutionary changes in parasites regarding parts of their morphology and their skills to parasitize their hosts.

Types Of Parasites

Another view of parasites and their classification is based on the place one occupies in the organism of the other and how obligatory the dependence on the host is.

Endoparasites Vs. Ectoparasites

Endoparasites: These are organisms that dwell within the host’s living organism for instance; tapeworms are found within the digestive tracts while Plasmodium, the malaria parasite is present within the blood vessels. Endoparasites may have a rather rich life cycle and can infect almost any internal organ.

Ectoparasites: These parasites are those which attach themselves to the skin or hairs of the host for instance fleas, ticks and lice. Ectoparasites are parasites that live on the host’s skin or outer layer of tissues and survive by drawing blood or other sustenance from the exterior environment.

Obligate Vs. Facultative Parasites

• Obligate Parasites: These parasites have their life cycle incomplete without a host on which they lay their eggs or have their young feed. These species are completely parasitic, meaning that their entire existence, growth, and process of reproducing comes from their host. These include viruses and some bacteria.

• Facultative Parasites: These organisms can exist as free-living and parasitic too, and are known to be very sensitive to pressure. Although they are parasitic and can parasitize their host till dangerous if they get a chance, they can survive without a host. An example is the free-living amoeba Naegleria fowleri which has the potential to cause infection if specific circumstances arise.

Examples Of Parasitic Symbiosis

The examples are listed below-

Parasitic Plants

Example: Mistletoe

One of the most familiar examples of parasitic plants is the mistletoe which grows on trees and shrubs enveloping their branches. This is a parasitic plant that feeds on water and nutrients from its host thus stunting the growth of this host plant and in some cases causing its death. Mistletoe has highly modified roots called haustoria which burrow into the tissues of the host to draw nutrients.

Image of mistletoe on a tree

Parasitic Animals

Example: Tapeworms in intestines

Tapeworms are worms of the platyhelminth group which are parasitic and survive inside the gut of hosts such as humans and animals. These worms remain in the intestine of the host by hooks and suckers and feed on the contents of the intestine through the skin. The affliction of tapeworms causes deficiency diseases and other illnesses in the host organism.

Image of a tapeworm

Parasitic Fungi

Example: Cordyceps affecting insects

Cordyceps is a family of mycopathogens that parasitize insects and other Arthropods. The spores land on the host’s body, penetrate it and the bacteria bring out fruiting bodies to attack the host and emerge from its dead body to disperse more spores. Such significant distortions of the host’s behaviour and physiology are characteristic of Cordyceps.

Image of Cordyceps on an insect

Parasitic Symbiosis In Humans

Common Human Parasites

Protozoa (e.g., Giardia)

Giardia: Another protozoan parasite is Giardia lamblia which results in giardiasis which is a gastrointestinal affliction. It is caught when you consume contaminated water or food and it fixes itself on the small intestine; the symptoms are usually diarrhoea, stomach aches, and nausea.

Helminths (e.g., Schistosoma)

Schistosoma: Schistosoma is a group of parasitic flukes that affect humans. They are commonly referred to as blood flukes and cause the disease referred to as schistosomiasis. These worms stay within the blood vessels of their hosts and the eggs they release . .. can cause inflammation and organ damage. Transmission is via water sources containing the protozoan parasites such as Schistosoma species, in this case, fresh water.

Diagnosis and Treatment

Common Diagnostic Methods

Microscopy

Microscopy, in which the doctor looks directly at material from the patient’s stool, blood, or tissues to find parasite eggs, larvae or adult parasites. It is applicable in diagnosing infections like giardiasis and schistosomiasis For people with the disease, the doctor examines their stools through a microscope to detect the presence of the organism causing the infection.

Serology

Serological tests for the parasitic disease look for antibodies or antigens within the bloodstream. Serodiagnosis can be useful in diagnosing infection when the parasite(s) is not easily found.

Treatments And challenges

• Treatments: Some of the drugs used in antiparasitic include metronidazole in the treatment of giardiasis and praziquantel in the treatment of schistosomiasis. These drugs aim at destroying the helminth’s life cycle and assist in eliminating the parasites.

• Challenges: Antibiotic resistance is an issue, which is why some parasitic infections become more difficult to control. Also, healthcare intervention such as access to effective drugs and diagnostic equipment in some parts of the world is scarce, thus making disease control measures a challenge.