QCAA - Ecosystem Dynamics (EA MCQs)

The table provides population data for a species of fairy-wren. The population growth rate in 2022 was closest to:

• 17%

• 27%

• 55%

• 73%

• 27

• 48

• 54

• 60

Which of the figures below represents a logistic population growth of a species over time?

• A

• B

• C

• D

An ecological niche refers to

• a group of organisms competing for the same resources.

• the role and space that an organism fills in the ecosystem.

• all organisms occupying the physical space close enough to interact with each other.

• the largest population of a particular species that can be supported by an ecosystem.

Transfer efficiency between producers and primary consumers is closest to

• 5%

• 10%

• 12%

• 16%

What is used directly by plants for protein synthesis?

• nitrite, NO₂^-

• nitrate, NO₃^-

• ammonia, NH₃

• atmospheric nitrogen, N₂

The competitive exclusion principle applies to different species occupying the same

• niche.

• habitat.

• environment.

• trophic level.

A keystone species is defined as a species that

• is the top predator in an ecosystem.

• is a major producer in an ecosystem.

• has a unique and crucial role in an ecosystem.

• directly influences all species in an ecosystem.

The carrying capacity of an ecosystem refers to the

• total biomass of primary producers in an ecosystem at a given time that supports the higher trophic levels.

• size of a population that can be supported indefinitely on the available resources and services of that ecosystem.

• number of individual top predators in the ecosystem at a given time that can be supported by the lower trophic levels.

• maximum population of individuals of different species that the ecosystem can support for an extended period of time.

The table provides population statistics for a species of tree kangaroo in northern Queensland.

Determine the population growth rate for tree kangaroos in 2017.

• 14.6%

• 15.0%

• 26.5%

• 86.9%