Topic Test Topic Test Review
For which method of determining population size is the population not aware of the sampler's presence? a. mark/recapture b. direct observation c. sampling d. indirect observation
D.indirect observation
How does a logistic growth curve differ from an exponential growth curve?
A logistic growth curve is S-shaped. Populations that have a logistic growth curve will experience exponential growth until their carrying capacity is reached, at which point their growth begins to level. An exponential growth curve is J-shaped. Exponential growth is more common in R-selected species, which have a short life span and a high rate of reproduction.
Explain how the method of mark and recapture works to determine population size.
A number of members of a population are capture, tagged, and released. At a later time, the sampler returns and captures a set number of members of the population and determines the ratio of tagged to untagged individuals.
Which of the following conditions would lead to a small population size? a. a low birth to death ratio b. a high birth to death ratio c. immigration d. large number of resources
A. a low birth to death ratio
Population density is calculated by _______. a. dividing the number of organisms in a region by the land area b. multiplying the number of organisms in a region by the land area c. dividing the land area by the number of organisms in the region d. by subtracting the land area from the number of organisms in a region
A. dividing the number of organisms in a region by the land area
Orange trees planted in an orchard would most likely fall in which category of population distribution? a. even b. random c. clumped d. density
A.even
Which of the following selection pressures is responsible for the limited evolutionary changes experienced by alligators and other crocodilians? a. stabilizing selection b. directional selection c. disruptive selection d. high mutation rate
A.stabilizing selection
Which of the following species is an R-selected species? a. Giant tortoises b. Mosquitoes c. Elephants d. Redwoods
B. Mosquitoes
There are approximately 35,000 bald eagles in Alaska, which covers 586400 square miles. What is the population density for the bald eagles in Alaska? a. 17 bald eagles per square mile b. 0.04 bald eagles per square mile c. 0.06 bald eagles per square mile d. 1 bald eagle per square mile
C.0.06 bald eagles per square mile
Which of the following species would you most expect to be distributed according to a regular pattern? a. termites b. stingless bees c. fish d. creosote bushes
D. creosote bushes
Which of the following is most likely an example of genetic drift resulting from the founder effect? a. The species' physical habitat is limited. b. The population expresses a mix of dominant and recessive traits. c. The species occupies a small, specific niche. d. A population commonly expresses traits that are otherwise rare in the species.
D.A population commonly expresses traits that are otherwise rare in the species.
Which of the following statements about logistic growth curves is true? a. Logistic growth curves are common for R-selected species. b. Logistic growth curves are J-shaped. c. No organisms in nature experience logistic growth rates. d. Logistic growth curves increase exponentially at first, then experience slowed growth rates.
D.Logistic growth curves increase exponentially at first, then experience slowed growth rates.
Bottleneck events are always caused by the death of most of a species' population.
False
The total number of organisms an ecosystem can support is its tolerance range.
False
What distinguishes disruptive and directional selection pressures when both select for extreme genetic traits?
While directional selection selects for extreme variation of one genetic trait in a population, disruptive selection selects for both extremes. Disruptive selection eliminates intermediate traits leading to selection at either extreme. Directional selection, meanwhile, preferentially selects for individuals expressing the extreme trait.