Flashcards in Introduction Deck (20):
Organism that lives ON (external) or IN (internal) and at the expense of another organism (the HOST)
Definitive (Final) Host:
The host in which the parasite adults undergo sexual reproduction.
Usually the host in which only immature (asexual) stages of the parasite occur.
Paratenic (Transport) Host
A potential intermediate host in which there is no development of the immature parasite; the host does not favor nor hinder the parasite in the completion of its life cycle.
An infected definitive host (animal) serving as a source from which other animals or man can become infected.
transfer does not require an intermediate host
requires an intermediate host in which development occurs
Type of symbiosis
Host is usually injured to some degree
Protozoa: in Kingdom Protista
Single celled organisms – usually microscopic, complex.
move by flagella(e)
move by cytoplasmic protrusions called pseudopodia
(many free living, many parasitic)
All intracellular parasites
cell surface covered with rows of cilia
Trematoda flatworms – Flukes
Thick oval, leaf shape is most common
All except Schistosoma contain both ovaries and testes
Cestoidea – Tapeworms
Most common form is elongated, ribbon-like
Growth of worm begins from segments being budded off anterior end, called scolex
Larval forms called metacestodes develop in intermediate hosts
Cylindrical worms, separate sexes
May or may not require intermediate hosts
Have five larval stages
Thorny proboscis separates them from nematodes
insecta and arachnida
Insecta: Adults have 6 legs & segmented body