4.5 Community Ecology I

Question 1: Corals are marine invertebrates (phylum Cnidaria) that form colonies of

interconnected polyps. Many species of coral have a beneficial relationship with algae called zooxanthellae. The corals provide this algae with a place to live and the algae provides nutrients derived from photosynthesis to the corals. Which of the following would best describe this relationship?

A. Predator/prey

B. Commensalism

C. Mutualism

D. Parasitism

C. mutualism

what is a community

• A group of populations/species found in the same geographic space at the same time

• These populations/species interact with each other and their environment (abiotic and biotic features)

• Boundaries aren’t always clearly defined

Do all communities across the Earth look the same?

No, communities are unique in different parts of the Earth. And yet, while the ‘players’ are often distinct, the ‘roles’ are often similar.

What is biodiversity?

• The variety of life on Earth at all its levels, from genes to ecosystems.

• This concept can encompass the evolutionary, ecological, and even cultural processes that sustain life.

• can be looked at through many different levels

what is this called?

food chain

Question 2: The interaction between the predatory bird and the fish below it (in image above) is a ______________ interaction.

A. Interspecific

B. Intraspecific

interspecific

what does interspecific mean?

when you are interacting between species

what does intraspecific mean?

interacting within species

what is a food web

what is Competitive exclusion principle

When two species compete for the same food resource, one of the two competitors is likely to come out the loser.

what is Niche differentiation

When competition occurs between species, the competitors may end up specializing to reduce competition.

what is competition

Organisms of two species use the same limited resource and have a negative effect on each other. - / -

what is predation

A member of one species, predator, eats all or part of the body of a member of another species, prey + / -

what is herbivory

A special case of predation in which the prey species is a plant. + / -

what is mutualism

A long-term close association between two species in which both partners benefit.

+ / +

what is commensalism

A long-term close association between two species in which one benefits and the other is unaffected. + /

what is parasitism

A long-term close association between two species in which one benefits and the other is harmed. + / -

what is symbiosis

a very intimate relationship – where the two species essentially live on or in each other

what are examples of symbiosis

o Ant / tree mutualism (Azteca/Cecropia or Pseudomyrmex/acacia)

o Clownfish/ Sea anemone

o Fig tree/ fig wasp

o Eukaryotic cells: Prokaryote host with smaller prokaryotic symbiont

▪ Mitochondria

▪ Chloroplasts

Question 3: The interaction between the alien xenomorph and humans in the science fiction film, ‘Alien’ could probably be considered:

A. Predator/prey

B. Parasite/host

C. Mutualism

D. Commensalism

E. Competition

B. Parasite/host