AP®︎ Environmental Science: Unit 3 Practice Test
Prepare for your quiz, test, or the AP exam with focused practice questions on Unit 3 of AP Environmental Science – Populations.
Questions List
Unit 3 (All Topics)
Question 1 Topic 3.1Easy
This question tests the following: ERT-3.A
What type of species can easily adapt to various environments?
What You’re Being Tested On:
Explore the learning objectives taken directly from the College Board’s AP® Environmental Science Curriculum. Ensure you’re prepared for the exact topics covered on the AP® exam, in-class tests, and quizzes, and gain confidence in your mastery of the material.
Unit 3: Populations
This unit covers population dynamics, reproductive strategies, and how growth trends impact resource use and sustainability.
Topic 3.1: Generalist and Specialist Species
Learning Objective: ERT-3.A
Identify differences between generalist and specialist species.
Essential Knowledge: ERT-3.A.1
Specialist species tend to be advantaged in habitats that remain constant, while generalist species tend to be advantaged in habitats that are changing.
Topic 3.2: K-Selected r-Selected Species
Learning Objective: ERT-3.B
Identify differences between K- and r-selected species.
Essential Knowledge: ERT-3.B.1
K-selected species tend to be large, have few offspring per reproduction event, live in stable environments, expend significant energy for each offspring, mature after many years of extended youth and parental care, have long life spans/life expectancy, and reproduce more than once in their lifetime. Competition for resources in K-selected species’ habitats is usually relatively high.
Essential Knowledge: ERT-3.B.2
r-selected species tend to be small, have many offspring, expend or invest minimal energy for each offspring, mature early, have short life spans, and may reproduce only once in their lifetime. Competition for resources in r-selected species’ habitats is typically relatively low.
Essential Knowledge: ERT-3.B.3
Biotic potential refers to the maximum reproductive rate of a population in ideal conditions.
Essential Knowledge: ERT-3.B.4
Many species have reproductive strategies that are not uniquely r-selected or K-selected, or they change in different conditions at different times.
Essential Knowledge: ERT-3.B.5
K-selected species are typically more adversely affected by invasive species than r-selected species, which are minimally affected by invasive species. Most invasive species are r-selected species.
Topic 3.3: Survivorship Curves
Learning Objective: ERT-3.C
Explain survivorship curves.
Essential Knowledge: ERT-3.C.1
A survivorship curve is a line that displays the relative survival rates of a cohort—a group of individuals of the same age—in a population, from birth to the maximum age reached by any one cohort member. There are Type I, Type II, and Type III curves.
Essential Knowledge: ERT-3.C.2
Survivorship curves differ for K-selected and r-selected species, with K-selected species typically following a Type I or Type II curve and r-selected species following a Type III curve.
Topic 3.4: Carrying Capacity
Learning Objective: ERT-3.D
Describe carrying capacity.
Essential Knowledge: ERT-3.D.1
When a population exceeds its carrying capacity (carrying capacity can be denoted as K), overshoot occurs. There are environmental impacts of population overshoot, including resource depletion.
Learning Objective: ERT-3.E
Describe the impact of carrying capacity on ecosystems.
Essential Knowledge: ERT-3.E.1
A major ecological effect of population overshoot is dieback of the population (often severe to catastrophic) because the lack of available resources leads to famine, disease, and/or conflict.
Topic 3.5: Population Growth and Resource Availability
Learning Objective: ERT-3.F
Explain how resource availability affects population growth.
Essential Knowledge: ERT-3.F.1
Population growth is limited by environmental factors, especially by the available resources and space.
Essential Knowledge: ERT-3.F.2
Resource availability and the total resource base are limited and finite over all scales of time.
Essential Knowledge: ERT-3.F.3
When the resources needed by a population for growth are abundant, population growth usually accelerates.
Essential Knowledge: ERT-3.F.4
When the resource base of a population shrinks, the increased potential for unequal distribution of resources will ultimately result in increased mortality, decreased fecundity, or both, resulting in population growth declining to, or below, carrying capacity.
Topic 3.6: Age Structure Diagrams
Learning Objective: EIN-1.A
Explain age structure diagrams.
Essential Knowledge: EIN-1.A.1
Population growth rates can be interpreted from age structure diagrams by the shape of the structure.
Essential Knowledge: EIN-1.A.2
A rapidly growing population will, as a rule, have a higher proportion of younger people compared to stable or declining populations.
Topic 3.7: Total Fertility Rate
Learning Objective: EIN-1.B
Explain factors that affect total fertility rate in human populations.
Essential Knowledge: EIN-1.B.1
Total fertility rate (TFR) is affected by the age at which females have their first child, educational opportunities for females, access to family planning, and government acts and policies.
Essential Knowledge: EIN-1.B.2
If fertility rate is at replacement levels, a population is considered relatively stable.
Essential Knowledge: EIN-1.B.3
Factors associated with infant mortality rates include whether mothers have access to good healthcare and nutrition. Changes in these factors can lead to changes in infant mortality rates over time.
Topic 3.8: Human Population Dynamics
Learning Objective: EIN-1.C.1
Explain how human populations experience growth and decline.
Essential Knowledge: EIN-1.C.1
Birth rates, infant mortality rates, and overall death rates, access to family planning, access to good nutrition, access to education, and postponement of marriage all affect whether a human population is growing or declining.
Essential Knowledge: EIN-1.C.2
Factors limiting global human population include the Earth’s carrying capacity and the basic factors that limit human population growth as set forth by Malthusian theory.
Essential Knowledge: EIN-1.C.3
Population growth can be affected by both density-independent factors, such as major storms, fires, heat waves, or droughts, and density-dependent factors, such as access to clean water and air, food availability, disease transmission, or territory size.
Essential Knowledge: EIN-1.C.4
The rule of 70 states that dividing the number 70 by the percentage population growth rate approximates the population’s doubling time.
Topic 3.9: Demographic Transition
Learning Objective: EIN-1.D
Define the demographic transition.
Essential Knowledge: EIN-1.D.1
The demographic transition refers to the transition from high to lower birth and death rates in a country or region as development occurs and that country moves from a pre-industrial to an industrialized economic system. This transition is typically demonstrated through a four-stage demographic transition model (DTM).
Essential Knowledge: EIN-1.D.2
Characteristics of developing countries include higher infant mortality rates and more children in the workforce than developed countries.
