Question 1

Kudzu,an Asian vine introduced to the United States in the 1930s as a means to control erosion,is referred to as "the plant that ate the South" because it grows so fast and overtakes most plant species in its path.A recent and unusual way that some people are using to control kudzu growth is to allow goats to graze their land and eat the kudzu,roots and all.This is considered by some to be the most environment-friendly way to eliminate this invasive vine.How can we best describe the goats in this situation?

Accepted Answer

A) a threatened species 
B) an invasive species 
C) a biological control agent 
D) an integrated pest management agent

Question 2

If a population's growth rate decreases as the population size approaches carrying capacity,the population's growth follows a(n)________ model.

Accepted Answer

A) exponential 
B) boom-and-bust 
C) logistic 
D) density-independent

Question 3

Which of these is a characteristic of Type I survivorship?

Accepted Answer

A) There is low survivorship for the very young. 
B) Most individuals survive to older age intervals. 
C) Survivorship is constant over the lifespan. 
D) Survivorship is high for the few individuals that survive to a certain age.

Question 4

Non-native species can have important effects on biological communities by ________.

Accepted Answer

A) preying upon native species only 
B) competing with native species for resources only 
C) reducing biodiversity only 
D) All of these are effects that non-native species can have on biological communities.

Question 5

Chinese privet is a plant that is native to China.Over 150 years ago,Chinese privet was introduced to the United States as a fast-growing shrub that serves as an excellent privacy hedge.With no natural predators,Chinese privet quickly established itself and spread in natural areas throughout the southeast and eastern seaboard of the United States.Its dominance in these areas has jeopardized the survival of native plant species.Chinese privet provides evidence that ________.

Accepted Answer

A) introducing non-native organisms can cause environmental damage 
B) American gardeners can easily control the spread of Chinese privet 
C) integrated pest management strategies will not decrease Chinese privet populations 
D) non-native plant species have Type I survivorship curves

Question 6

The Endangered Species Act aims to help protect species that ________.

Accepted Answer

A) are in danger of extinction 
B) dominate suitable habitats 
C) compete with invasive species 
D) are economically valuable

Question 7

Most crop pests ________.

Accepted Answer

A) have an opportunistic life history 
B) have an equilibrial life history 
C) exhibit type I survivorship 
D) consist of long-lived individuals

Question 8

A study of the human ecological footprint conducted by the World Wildlife Fund in 2008 shows that ________.

Accepted Answer

A) we have already exceeded the planet's biocapacity per person 
B) we are far below the planet's biocapacity per person 
C) Earth can sustain a population about double the current population 
D) the human population will soon crash

Question 9

Please read the following scenario to answer the following questions.
Michigan's Isle Royale is an island located in Lake Superior that is 45 miles long and 9 miles wide.Ecologists estimate that the moose population on the island has been there since around 1900.The wolf population on the island,on the other hand,has been there only since the winter of 1949.Weather conditions had to be calm and cold enough for the lake to freeze and the first wolves to make the passage over to the island.When the wolves arrived,they were greeted with a large moose population that had no predators.The moose population was at a dangerously high level,but was kept in check by the arrival of the wolves.This "harmonious" pattern continued for at least 20 years.
In 1982,the wolf population suddenly crashed.The problem was a new canine virus.This virus surfaced around the world in 1978 and spread rapidly in about 6 months.Infected animals can survive,but they have to be treated immediately.Ecologists hypothesized that the virus arrived on the island carried on the shoe of a human traveler.The wolf population decreased from 50 to 14 individuals in a year.While the wolf population dropped,the moose population increased.However,the winter of 1996 was extremely harsh and the moose population experienced a major crash.More than 500 animals died during the winter months,reducing the population to less than 800 animals.
-During a 1-year study,a graduate student attempted to count the wolves and moose on the island.He estimated that there were 950 moose and 120 wolves.How many organisms,populations,and species were included in this study?

Accepted Answer

A) organisms = 2; populations = 1; species = 2 
B) organisms = 1,070; populations = 1; species = 2 
C) organisms = 2; populations = 2; species = 1,070 
D) organisms = 1,070; populations = 2; species = 2

Question 10

In most developing countries,________.

Accepted Answer

A) birth rates equal death rates,so the population is fairly stable 
B) birth rates are lower than death rates,so the population is declining 
C) birth rates are lower than death rates,so the population is growing rapidly 
D) birth rates are much higher than death rates,so the population is growing rapidly

Question 11

You arrive back in the United States after having visited a foreign country located on another continent.The customs agent stops the person in front of you and confiscates the fruit basket this person is bringing home.Being the knowledgeable person you are,you calmly explain to your enraged fellow traveler that the reason for the detainment is that the fruit basket may be ________.

Accepted Answer

A) carrying endangered fruit 
B) carrying a non-native species that could damage North American ecosystems 
C) contaminated with CFCs that will damage the ozone layer above North America 
D) contaminated with sufficient DDT to cause serious harm to anyone who eats the fruit

Question 12

Type I survivorship curves are typical of species that exhibit ________.

Accepted Answer

A) an intermediate number of offspring and an intermediate level of parental care 
B) few offspring and good parental care 
C) many offspring and good parental care 
D) many offspring and poor parental care

Question 13

The red-cockaded woodpecker,an endangered species,is dependent upon ________ for maintenance of its source habitat.

Accepted Answer

A) thick vegetation at least 15 feet in height 
B) fire 
C) floods 
D) corn snakes

Question 14

In an ideal,unlimited environment,a population's growth follows a(n)________ model.

Accepted Answer

A) exponential 
B) density-dependent 
C) logistic 
D) boom-and-bust

Question 15

Integrated pest management ________.

Accepted Answer

A) favors overwhelming a pest with chemical pesticides 
B) advocates total eradication of pest species 
C) aims to keep pest populations on an exponential growth curve 
D) advocates mixed-species plantings and rotating crops

Question 16

This graph represents three different populations.Use it to answer the following questions.
 
-If all populations occupy different areas that are approximately the same size,which population will have the lowest density after 3 years?

Accepted Answer

A) Population A 
B) Population B 
C) Population C 
D) After 3 years,all three populations will have the same density.

Question 17

In an ideal,unlimited environment,what shape does a population's growth curve most closely resemble?

Accepted Answer

A) S 
B) J 
C) ∧ 
D) ∪

Question 18

Examples of invasive species include ________.

Accepted Answer

A) kudzu and red-cockaded woodpeckers 
B) cod and Chilean sea bass 
C) snowshoe hares and kudzu 
D) cheatgrass and Burmese pythons

Question 19

During the Pleistocene era,many large mammal species went extinct.Their permanent disappearance occurred in a short period of time when humans were expanding across North America.In this situation,how do many scientists view humans?

Accepted Answer

A) as a threatened species 
B) as a density-independent factor 
C) as an invasive species 
D) as a biological control agent

Question 20

According to the logistic growth model,what happens to a population when the size of the population reaches carrying capacity?

Accepted Answer

A) The growth rate increases. 
B) The growth rate decreases. 
C) The growth rate cannot be determined. 
D) The growth rate is zero.

Exam 19: Population Ecology

If a population's growth rate decreases as the population size approaches carrying capacity,the population's growth follows a(n) ________ model.