CLEP Biology Ecology & Evolutionary Processes 2

Question 1

Which type of symbiosis occurs when one organism benefits and the other is neither helped nor harmed?

Accepted Answer

Commensalism

Answer

Commensalism is a symbiotic relationship where one species benefits and the other experiences no significant effect.

Question 2

The competitive exclusion principle states that two species competing for the same limited resource cannot:

Accepted Answer

Coexist in the same habitat indefinitely

Answer

Gause's competitive exclusion principle holds that two species occupying the exact same ecological niche cannot stably coexist — one will outcompete and displace the other.

Question 3

In a food web, which trophic level contains the greatest total biomass?

Accepted Answer

Primary producers

Answer

Primary producers (plants and other autotrophs) form the base of the energy pyramid and contain the greatest biomass because energy is lost at each trophic level.

Question 4

Which evolutionary mechanism results in the random change of allele frequencies in a small population?

Accepted Answer

Genetic drift

Answer

Genetic drift refers to random fluctuations in allele frequencies that are especially pronounced in small populations, potentially causing alleles to be lost or fixed by chance.

Question 5

The concept of 'survival of the fittest' in evolutionary biology most precisely means:

Accepted Answer

Individuals with the highest reproductive success in their environment

Answer

Fitness in evolutionary biology refers specifically to an organism's reproductive success — its ability to survive and pass on its genes to the next generation.

CLEP Practice Test

CLEP Practice Test

CLEP Biology Ecology & Evolutionary Processes 2