Question: What Is A Definitive Host In The Life Cycle Of A Parasite?

Which parasite has the most complex life cycle?

Lancet liver flukeDicrocoelium dendriticum, commonly called the Lancet liver fluke, is a parasitic fluke that displays one of the most complex parasitic life cycles currently known.

The Lancet liver fluke lives mainly in cows and sheep, but is also found in other herbivorous mammals and, in rare cases, has been known to infect humans..

What does parasite mean?

1 : a living thing (as a flea, worm, or fungus) that lives in or on another living thing and gets food and sometimes shelter from it and usually causes harm to it. 2 : a person who lives at the expense of another. parasite.

How are parasites transmitted?

Parasitic infections can be spread in a number of ways. For example, protozoa and helminths can be spread through contaminated water, food, waste, soil, and blood. Some can be passed through sexual contact. Some parasites are spread by insects that act as a vector, or carrier, of the disease.

How do parasites reproduce in humans?

Most parasites reproduce asexually, but they can switch to sexual reproduction to encourage diversity and to remain infectious. Certain species of parasites can even sexually reproduce with other species, via a process called hybridization.

What is an intermediate host in the parasite life cycle?

Secondary or intermediate host – an organism that harbors the sexually immature parasite and is required by the parasite to undergo development and complete its life cycle. It often acts as a vector of the parasite to reach its definitive host.

What is the infective stage of parasite?

The chapter describes the ensheathed larva and the egg as infective stages. The sensory physiology of the infective larva must differ from that of other stages, because it must be able to “recognize” its host. The probability that infection will occur may be strongly affected by the behavior of infective larvae.

Why do parasites have complex life cycles?

Complex cycles necessitate high predation rates on each host, giving high transmission to the next host in the chain. Direct cycles will typically have free-living stages with a high probability of the parasite reaching its definitive host.

What is an intermediate host of a parasite?

1 : a host which is normally used by a parasite in the course of its life cycle and in which it may multiply asexually but not sexually — compare definitive host.

What type of host temporarily harbors the larval asexual or immature stages of a parasite?

Intermediate hostCardsTerm SymbiosisDefinition association between two organisms of different species either temporary or permanent.Term Intermediate hostDefinition a host that harbors the larval, juvenile, immature, or asexual stages of the parasite.Term EncystedDefinition where a parasite does not change, but remains arrest.101 more rows•Jan 10, 2012

What is the advantage of a parasitic life cycle?

Required by some parasites to complete their life cycle, Advantages of an intermediate hosts include: increasing the spread of the parasite & protecting the parasite from spending too much time in the environment. What is the intermediate host in the life cycle of the Heartworm?

What is the definitive host of a parasite?

The definitive host is the one which harbors the adult parasite and where the parasite reproduces sexually. The intermediate host is the host which harbors the larval stage or the asexual forms of the parasite. Few parasites require two different intermediate hosts in addition to a definitive host.

What is a definitive host in the life cycle of a parasite quizlet?

Definitive host. Host in which the parasite reaches the adult stage or undergoes sexual reproduction. If there is no sexual reproduction in the life of the parasite, the host most important to humans is the definitive host.

What is the life cycle of malarial parasite?

The malaria parasite life cycle involves two hosts. During a blood meal, a malaria-infected female Anopheles mosquito inoculates sporozoites into the human host . Sporozoites infect liver cells and mature into schizonts , which rupture and release merozoites . (Of note, in P.

What is meant by the life cycle of a parasite?

All parasites have a life cycle that involves a period of time spent in a host organism and that can be divided into phases of growth, reproduction, and transmission. Life cycles of parasites can be further divided into two categories: direct (monoxenous) and indirect (heteroxenous).

How long can a parasite live?

Tapeworms embed their heads into the intestinal wall and remain there. From there, certain types of tapeworms can produce eggs that mature into larvae that migrate to other parts of the body. A tapeworm looks like a long, white ribbon. They can grow up to 80 feet long and live in a human for up to 30 years.