Definitive host

Definition

A definitive host is an organism in which a parasite reaches its adult form and undergoes sexual reproduction. This host is crucial for the completion of the parasite's life cycle.

5 Must Know Facts For Your Next Test

1. Definitive hosts are essential for the sexual reproduction of parasites.
2. Humans can be definitive hosts for several parasites, such as Plasmodium species causing malaria.
3. In the life cycle of many parasites, there can be multiple intermediate hosts but only one definitive host.
4. The identification of a definitive host helps in understanding disease transmission pathways and control measures.
5. Without a definitive host, certain parasites cannot mature or reproduce sexually.

Review Questions

• What role does a definitive host play in the life cycle of a parasite?
• Can humans serve as definitive hosts? Provide an example.
• Why is it important to identify the definitive host in disease epidemiology?

Related terms

Intermediate Host:

An organism that harbors the larval or asexual stages of a parasite.

Reservoir Host: An organism that harbors a pathogen without succumbing to disease, serving as a source of infection.

Vector:

An agent, often an arthropod, that transmits pathogens from one host to another.