Biology 172 Quiz 18: Ecological Principles

A population in r-phase growth exhibits the following population size changes (see table below). What would the population size be in year 4?

A.108
B.72
C.54 
D.60 
E.162 

According to the Competitive Exclusion Principle 
A.predators will be eliminated by competition with their prey 
B.no two similar species can occupy the same niche at the same time in the same place 
C.species competing for common resources will form agreements to share these resources
D.mutations will lead to species extinction
E.no two different species ever compete for the same resources 

In a typical ecosystem, the second trophic level consists of 
A.primary producers 
B.carnivores
C.herbivores
D.hydrothermal vents 
E.decomposers 

In the carbon cycle, the decomposers utilize ______ as their primary source of carbon. 
A.live plants
B.inorganic carbon 
C.organic carbon from dead organic matter 
D.carbon dioxide 
E.radioactive carbon-14

The concept of trophic structure of a community emphasizes the 
A.keystone predator 
B.species richness of the community
C.feeding relationships within a community
D.effects of coevolution 
E.prevalent form of vegetation 

The niche of an organism is best defined as that organism's 
A.food resources 
B.habitat 
C."profession" or role in the ecosystem 
D.philosophy of life
E.diet

When an ecosystem develops on a new or highly altered surface (e.g., lava flow or burned-down forest floor) and then is transformed through time, eventually reaching an equilibrium, climax state, the phenomenon is know as
A.predation
B.competitive exclusion 
C.species displacement 
D.ecological succession 
E.coevolution 

Which biome type is characterized by the following features: midlatitudes, somewhat coastal, seasonal rainfall with occasional long dry spells, cool winters & hot summers? Note, this biome is dominated by drought resistant shrubs and trees. 
A.chaparral 
B.savanna
C.coniferous forest 
D.tropical forest
E.tundra 

Which component of the nitrogen cycle converts N2 into forms of nitrogen useable by plants?
A.decomposer
B.primary producer 
C.nitrogen-fixers 
D.denitrifiers 
E.primary consumer 

Which of the following best describes the fate of energy in an ecosystem? 
A.Energy is destroyed during biological energy transformations. 
B.Energy is released in the form of radioactivity.
C.Energy is continuously recycled. 
D.New energy is created as a consequence of living metabolism. 
E.Energy is degraded into a form less capable of doing work by living things (e.g., light is converted to heat).

You are most likely to find a species within its _______ of an environmental gradient.
A.zone of intolerance 
B.optimum range 
C.zona pelucida
D.zone of physiological stress 
E.zone of mortality 

Density-dependent factors influencing population growth include 
A.stress
B.production of toxic wastes 
C.limiting resources such as food and shelter 
D.spread of infectious diseases 
E.all of these

The classic S-shaped logisitic population growth curve equation incorporates which of the following variables? 
A.the intrinsic rate of increase (r) 
B.the carrying capacity (K) 
C.age at first reproduction
D.both A & B above 
E.answers A, B & C above

Which ecosystem type is LEAST subject to failure if one of its species is removed? 
A.terrestrial desert
B.African savanah
C.cave
D.arctic tundra 
E.tropical rainforest 

Which of the following is a biotic factor influencing the success of a species? 
A.the occurrence of catastrophic events like earthquakes 
B.competition with other species 
C.temperature 
D.water availability
E.salinity