Chapters 38-40 - Community and Ecosystem Ecology

Question 1

What is a biological community?

Answer 1

A community that includes all of the populations of various organisms live close enough for potential interaction

Question 2

What 2 things does biodiversity depend on?

Answer 2

1. Species richness (number of different species)
2. Relative abundance (proportional representation of a species)

Question 3

What are interspecific interactions

Answer 3

Relationships with individuals of other species

Question 4

What is interspecific competition?

Answer 4

When species of different ecological niches overlap, and common resources are limited since they both require that resource

Question 5

What is competitive exclusion?

Answer 5

When one species out competes and eliminates the competitor for the resource that they both require.

Question 6

What is co evolution?

Answer 6

When a change in one species act as a new selective force on another species, resulting in it evolving as well.

Question 7

What are scavengers?

Answer 7

Large animals that feed on carcasses

Ex. Wolf

Question 8

What are detritivores?

Answer 8

Animals that eat decaying organic materials such as animal waste, plant litter, bodies of small dead organisms

Ex. Earthworms

Question 9

What are decomposers?

Answer 9

Animals that breakdown and digest dead/decaying organisms and provide raw material for producers to use.
(usually smaller pieces that have already been broken down by detritivores)

Ex. Fungi

Question 10

What is a keystone species?

Answer 10

A species whose impact on its community is much larger than its biomass or abundance would indicate.

(Holds the rest of it community in place)

Ex. Sea otters in the kelp community

Question 11

What is a trophic cascade?

Answer 11

When the removal of one species leads to effects for various other levels of the trophic structure

Ex. Removing a quaternary consumer will result in overpopulation of the animal is would normally eat

Question 12

What are the 3 types of symbioses?

Answer 12

1. Mutualism - both species benefit from relationship
2. Parasitism - only one species benefits while the other is harmed
3. Commensalism - one species benefits while the other is neither harmed nor benefits

Question 13

How much usable energy is used up at each trophic level?

Answer 13

Approx. 10x loss at each level