Question 1

Conditions whose growth-limiting effects increase as a population grows are density-independent factors.

Accepted Answer

Density-dependent factors increase in importance as population density increases.

Question 2

Source: Data from U.S. Census Bureau, International Data Base
-Based upon the age structure diagram,you expect the Indian population to

Accepted Answer

More people coming to reproductive age means more babies for the next generation.

Question 3

Which is an example of an aquatic ecosystem?

Accepted Answer

Ecosystems include living and non-living factors.

Question 4

Hydra,a type of cnidarian,have equal survival rates through life because they are equally fit at all stages.Hydra are an example of an organism with a type ________ survivorship curve.

Accepted Answer

When death is distributed uniformly across the lifespan in a population, that is a type II survivorship curve.

Question 5

Which of the following is an example of an aquatic community?

Accepted Answer

A community consists of all the populations of organisms interacting in an area.

Question 6

Based on the information provided,which of these would not be considered a species with an equilibrium life history?

Accepted Answer

Among other factors, equilibrium species are those that care for their young for an extensive period after birth.

Question 7

Which of the following is not a characteristic for an organism with an opportunistic life history?

Accepted Answer

In opportunistic life history, the offspring receive little parental care.

Question 8

Oysters and many other mollusks produce many offspring of which only a few survive to adulthood and then have little risk of predation with their strong adult shells.Oysters are an example of an organism with a type ________ survivorship curve.

Accepted Answer

Type III survivorship curves show high early mortality and low mortality later in life.

Question 9

Why have human growth rates increased the most in developing countries in the past 50 years?

Accepted Answer

Contrary to popular misconceptions, the recent increases in world population have been due to longer life spans rather than high birth rates.

Question 10

A country's ecological footprint can be calculated by multiplying its population size by the footprint of each individual.Why are some ecologists concerned about the ecological footprint of a country like India?

Accepted Answer

India's ecological footprint is a concern because its population is increasing, which, when multiplied by the footprint of each individual, could lead to a larger overall ecological footprint and potentially exceed the country's biocapacity.

Question 11

When exponential growth is plotted over time an S-shaped curve emerges.

Accepted Answer

An S-shaped curve is characteristic of logistic growth.

Question 12

Researchers studying guppies in Trinidad found that guppies in streams with high predation reproduced earlier and more frequently.Which of the following is most important in driving the guppies to change their life history in face of predation?

Accepted Answer

Having many offspring implies opportunism.

Question 13

Source: Data from U.S. Census Bureau, International Data Base
-Based upon the age structure diagram,you expect the Chinese population to

Accepted Answer

More people coming to reproductive age means more babies for the next generation, but fewer people coming to a reproductive age means less babies in the future.

Question 14

Which best describes the link between survivorship curves and opportunistic species?

Accepted Answer

Opportunistic species have many less-well-provided-for offspring and so are not subject to density-dependent factors.

Question 15

The overall human population growth rate is steadily increasing each year.

Accepted Answer

While the human population is increasing, the overall growth rate is declining.

Question 16

Which falls outside the study of ecology?

Accepted Answer

Ecology studies interactions, not biochemical structure, though such structures might explain what ecologists find.

Question 17

The maximum number of individuals of a population that a habitat can support indefinitely is its carrying capacity.

Accepted Answer

Carrying capacity is determined by the availability of key resources such as space and energy.

Question 18

Source: Data from U.S. Census Bureau, International Data Base
-Based upon the age structure diagram,you expect the American population to

Accepted Answer

Constant numbers in each age cohort leads to a stable population.

Question 19

When exponential growth is plotted over time a J-shaped curve emerges.

Accepted Answer

Exponential growth continues to increase very rapidly.

Question 20

Ecologists study

Accepted Answer

Ecology can study any organisms, though a particular study is usually limited to a few.

Quiz 18: Populations