Parasitism

Definition

Parasitism is a symbiotic relationship where one organism (the parasite) benefits at the expense of another organism (the host). This interaction often leads to harm or disease in the host.

5 Must Know Facts For Your Next Test

1. Parasitism can occur in both prokaryotic and eukaryotic organisms, including bacteria, fungi, protozoa, and helminths.
2. Parasites can be obligate (requiring a host to complete their life cycle) or facultative (can live both with or without a host).
3. Common examples of parasitic relationships include Plasmodium species causing malaria and various bacteria causing infections.
4. In microbiomes, parasitism can influence the composition and function of microbial communities within hosts.
5. The immune response of the host plays a crucial role in determining the outcome of parasitic infections.

Review Questions

• What are the two main types of parasites based on their reliance on a host?
• Give an example of a parasitic relationship involving a prokaryote or eukaryote.
• How does parasitism affect microbial community structures within hosts?

Related terms

Symbiosis:

A close and long-term biological interaction between two different biological organisms.

Mutualism:

A type of symbiosis where both organisms involved benefit from the relationship.

Commensalism:

A type of symbiosis where one organism benefits while the other is neither helped nor harmed.