Parasitism and Mutualism Exam Review

This set of flashcards covers key concepts from the lecture on Parasitism and Mutualism, along with related topics in community ecology.

What is parasitism?

A relationship where the parasite benefits while the host is harmed.

What are microparasites?

Small size parasites with a short generation time, such as viruses and bacteria.

What distinguishes hemiparasitic plants from holoparasitic plants?

Hemiparasitic plants are photosynthetic and depend on the host for water, while holoparasitic plants are non-photosynthetic and depend completely on the host for survival.

What are ectoparasites?

Parasites that live on the host's skin, such as fleas and lice.

Define direct transmission of parasites.

Transmission that occurs via direct contact with a carrier or through air, water, etc.

What is a vector-borne parasite?

Parasites that are transmitted between an intermediate host, where they develop, and a definitive host, where they reach maturity.

What are the impacts of parasites on their hosts?

They can cause behavioral changes, immune responses, reduction in fitness, and can regulate or extirpate populations.

What is mutualism?

A relationship in which both species involved benefit.

Differentiate between obligate and facultative mutualism.

Obligate mutualists cannot survive without the interaction, while facultative mutualists can survive independently.

What is species richness?

The number of different species in a community.

Define dominance in a community context.

Dominance occurs when a few species predominate within a community, often characterized by their abundance or biomass.

What is a keystone species?

A species whose impact on its community is much larger than its total mass or abundance, helping to hold the community in place.

What is a food web?

A more complex representation of feeding relationships among various species in a community, as opposed to a simple food chain.

How is Simpson's diversity index calculated?

It is calculated based on the probability that two randomly selected individuals belong to the same species, with a range from 0 to 1.