Intro to Parasitology Flashcards
What is symbiosis?
close association between different species (symbionts)
Who is Eugene Odum (1959) and what did he study?
studied effect on population growth: positive effect +, negative effect -, no effect 0
What is commensalism?
+/0 (one benefits/one experiences no effect), symbionts can live independently, ex: cattle and cattle egrets (birds) - cattle graze in field, stir up insects, egrets eat the insects
What is phoresies?
+/0 but travel together, pheraut - smaller, carried by host
What is mutualism?
+/+, obligatory, ex: termites - feed on wood, can’t digest it, intestinal protists secrete cellulase, cellulase digests the wood
What is exploition? What are the 3 types of exploiters?
+/-, predatory/prey: 1. parasitoid 2. mico predator 3. parasites
What is a parasitoid? Give an example
only one host attacked and killed. ex: adult female wasp deposits egg on/in insect, egg hatches, larval parasitoid feeds on the insect and consumes the host insect
What is a micro-predator? Give an example
attack many organisms but seldom kill them. ex: hematophagous organisms (blood feeding)
What are parasites?
only one host is attacked host seldom killed
What organisms are parasites?
- helminths (worms): cestodes & trematodes (flatworms), nematodes (roundworms) 2. protozoa 3. arthropods 4. chronic illness 5. difficult to control
What are not parasites?
bacteria, viruses, fungi
What is an ectoparasite?
on the surface of the host
What is an endoparasite?
inside the host
What is an obligate parasite?
must be parasitic for at least part of its life cycle
What is a facultative parasite?
not usually parasitic but can survive in host: ingested, in contact with orifice or wound
What is a definitive host?
where a parasite reaches sexual maturity. In parasite w no sexual reproduction DH is host that is most important to humans
What is an intermediate host?
required for the parasite’s development but parasite does not reach sexual maturity in this host
What is a parasite life cycle?
method for depicting the stages of a parasite & host(s) that it infects
What is a direct life cycle?
parasite passes from one DH to next DH via air, fomite, contaminated food/H2O
