An ecosystem is best defined as:

All organisms in an area
The non-living environment of an area
A community of organisms and their physical environment
Populations of the same species in one area

Habitat
Population
Niche
Community

Which of the following is a density-dependent limiting factor?

Natural disaster
Temperature
Competition for resources
Human activity

Which of the following is a density-independent limiting factor?

Predation
Disease
Competition
Flood

The maximum number of individuals that an environment can support is called its:

Growth rate
Reproductive potential
Carrying capacity
Biotic potential

A J-shaped population growth curve usually represents:

Logistic growth
Exponential growth
Declining growth
Stable growth

Which of the following represents logistic growth?

Unlimited growth with no limits
Growth that levels off at carrying capacity
Constant decline over time
Population cycles with no stabilization

Which type of species is most likely to be a pioneer species in succession?

Oak tree
Deer
Lichen
Wolf

When succession occurs in an area with no soil present, it is called:

Secondary succession
Primary succession
Tertiary succession
Climax succession

Secondary succession differs from primary succession because it:

Happens faster
Occurs where soil is already present
Often follows a disturbance like fire
All of the above

Which of the following is a keystone species?

A species with little effect on its ecosystem
A species that has a disproportionately large effect on ecosystem stability
A newly introduced invasive species
A primary consumer

A population crash occurs when:

A. A population grows past carrying capacity and resources collapse
B. Limiting factors suddenly reduce population size
C. Both A and B
D. Neither A nor B

The interaction in which both species benefit is called:

A. Commensalism
B. Parasitism
C. Mutualism
D. Predation

When one organism benefits and the other is unaffected, the interaction is called:

A. Parasitism
B. Mutualism
C. Commensalism
D. Competition

Which of the following is an example of parasitism?

A. Bee and flower
B. Bird nesting in a tree
C. Tapeworm in human intestine
D. Cheetah hunting gazelle

Which of the following can cause population change?

A. Birth rate
B. Death rate
C. Immigration/emigration
D. All of the above

A. Number of individuals in a population
B. Variety of species and genetic variation in an ecosystem
C. Number of prey species
D. Energy flow through a food web

An invasive species can affect an ecosystem by:

A. Increasing biodiversity
B. Outcompeting native species
C. Maintaining carrying capacity
D. Helping endangered species

Which type of growth is shown when a population increases slowly at first, then rapidly, before stabilizing?

A. Linear growth
B. Exponential growth
C. Logistic growth
D. Random growth