Unit 3 Topic 5 - Symbiosis Flashcards
what is symbiosis?
An ecological relationship between organisms of two different species that live in direct contact with one another
what is a symbiotic relationship?
an intimate relationship which has co-evolved over millions of years, there are three catagories of symbiosis; mutualism, parasitism and commensalism
what is parasitism?
a relationship where one organism, the parasite, benefits in the relationship ftom energy and nutrients and one organism, the host, is harmed
describe a parasite?
Parasites often have a limited metabolism meaning that most parasites cannot survive if they lose contact with their host. The most effective parasite is one that does not cause its host to die.
give an example of a parasite?
tapeworm- live and feed inside their host, dont have digestive systems of their own
flea- feels outside their host
how are parasites transmitted?
Direct Contact
Release of resistant stages
Use of a vector
what is a vector?
when a parasite uses another organism to reach their host for example, mosquitos carry malarial Plasmodium from human to human
what are resistant stages?
when parasite adapt to survive adverse environmental conditions until they come in contact with a new host for example, resistant larvae and pupae of the cat flea transmit the parasite to a new host
what is direct contact?
when parasites are passed to new host through physical contact, for example, head and body lice are easily passed from person to person
what is a direct parasitic lifecycle?
