Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

21 Cards in this Set

  • Front
  • Back
Define parasite
Living organism requiring prolonged contact with another living organism to meet some of its basic nutritional needs.

Include organisms of varying complexity from a unicellular protozoa to a complex multicellular helminth.
Define host
Organism harboring a parasite
Define definitive host
animal harboring the adult stage or sexually mature stage of a parasite
Define intermediate host
animal in which development of parasite occurs, but in which adulthood is NOT reached
Define life cycle
for survival and reproduction reasons many parasites evolve through a number of morphological stages and several environments or different hosts. The sequence of morphologic and environmental stages is referred to as the life cycle.
Define parasitic infection
invasion by endoparasites
(protozoa and helminths)
Define parasitic disease
invasion and pathology produced by endoparasites
Define parasitic infestation
external parasitism by ectoparasites (arthropods)
Define reservoir host
animal that harbors a species of parasite that can be transmitted to and infect man
Define vector
an arthropod or other living carrier that transports a pathogenic organism from an infected to a non-infected host. This can be passive transport or as an essential host in the life cycle of the pathogenic organism (i.e. - biological vector)
Define commensalism
association of two different species or organisms in which

one is benefited

other is neither benefited nor harmed
Define carrier
host that harbors a parasite but exhibits no clinical signs or symptoms
Define zoonosis
Disease involving a parasite for which the normal host is an animal

and wherein man can also be infected
Define protozoa
subkingdom consisting of


eukaryotic animals
List the phases of the parasite.

In which phase does the mechanism contributing to host-specificity occur?
Host localization


Growth and Reproduction

Occurs in all of them
T/F: Many parasites have complex life cycles with more than 1 host, vertebrate, and invertebrate hosts
In which host does sexual reproduction occur?
Definitive host
In which host does the LARVAL stages of the parasite develop?
Intermediate host
Can the larval stage have more than one intermediate host?
The life cycle of a parasite can be divided into what 3 phases?
- Host Localization

- Establishment

- Growth & Reproduction
The mechanisms that contribute to HOST Specificity can operate at which levels/phases of the life cycle?
All 3 levels