ch 53 pearson

Assume there are 200 MendAliens living on an island in my back yard. If my island has an area of 20 hectares, what is the population density of MendAliens in terms of MendAliens per hectare?

10: Population density is calculated as population size divided by area: 200 MendAliens / 20 hectares = 10 MendAliens per hectare.

You are doing a mark-recapture experiment to determine the population size of the MendAliens living on an island in my back yard. Initially, you catch and mark 130 MendAliens, which you then release. Next, you capture 90 MendAliens, of which 20 are marked. What is your estimate of the population size of MendAliens living on the island in my back yard?

585: To get the population size N, multiply the number marked in the first catch, M1, by the total number caught in the second catch, C, and divide that by the number of marked recaptures in the second catch, M2: N = (M1 x C) / M2 Or: (130 x 90) / 20 = 585.

Which of the following statements about density-independent growth is true?

Density-independent growth is also known as exponential growth.

Which factor does not affect a habitat's carrying capacity?

Genetic variation in the population

Which of the following statements about a population experiencing logistic growth is true?

If N is greater than KK, the population will shrink.

The average age of childbearing in country A is 26, whereas the average age in country B is 30. In each country, the average number of offspring per woman is 3. Which of the following statements about the population growth rate in each country must be true?

It is not possible to compare the population growth rates of countries A and B.

Which of the following is the most accurate statement on Earth's carrying capacity for humans?

Our technology has allowed the human population to keep increasing K.

Which of the following statements about age pyramids is true?

Predictions of a population's future take into account such factors as increasing survivorship and fecundity levels that remain the same.

In 1970, the average age of childbearing was 28, and the average number of offspring per woman was 3 in a certain country. In 1980, the average age of childbearing was still 28, but the average number of offspring per woman was 2 in that country. If the death rate in the country remained constant during those years, how did the population growth rate change from 1970 to 1980?

The population growth rate decreased.

Ignoring migration, the age structure diagram of a human population likely to maintain a relatively stable size will have what shape?

a rectangle tapering toward the top

Oyster populations are primarily, if not exclusively, composed of _____.

adults

Which of these was the first of the major events that stimulated an increase in the size of the human population?

advent of agriculture

Which of the following is an example of a population?

all the redwood trees that live in a forest

Which processes increase a population's size?

births and immigration

The number of individuals that a particular habitat can support with no degradation of that habitat is called _____.

carrying capacity

What are population dynamics?

changes in populations through time

In wild populations, individuals most often show a _____ pattern of dispersion.

clumped

Which of these organisms has a survivorship curve similar to that of humans?

elephants

Which of the following is regarded as a density-independent factor in the growth of natural populations?

flooding

Which of these organisms has a survivorship curve similar to that of oysters?

grasses

A broad-based pyramid-shaped age structure is characteristic of a population that is _____.

growing rapidly

Which factors have permitted the human population to continue increasing despite using nonrenewable resources at an unsustainable rate?

improvements in medical care, expansion of high-density urban areas

Which of these was the second of the major events that stimulated an increase in the size of the human population?

industrial revolution

Ignoring migration, the age structure of a human population likely to decrease in size will have what shape?

inverted pyramid

Which of the following conditions favors "big-bang" reproduction?

low rates of offspring survival

Resource competition, territoriality, disease, and toxic wastes are some of the factors that provide _____ and help regulate population.

negative feedback

In the models that describe population growth, r stands for _____.

per capita population growth rate

Ignoring migration, the age structure of a human population likely to increase in size will have what shape?

pyramid

Which of these species typically has a mortality rate that remains fairly constant over an individual's life span?

robins

The mark-recapture method would be best for sampling a population of _____.

sharks

To determine the density of a rabbit population, you would need to know the number of rabbits and _____.

size of area in which they live

Which of these was the third of the major events that stimulated an increase in the size of the human population?

the discovery of vaccines and the discovery of antibiotics

True or false? Factors that determine the per capita rate of increase of a population include the age of breeding and the number of offspring produced each year.

true

True or false? The growth rate of a certain population increases very quickly for a time and then levels off to zero. The most likely reason that the growth rate leveled off to zero is that the population reached the carrying capacity of that environment.

true

Under which of the following conditions would a population most likely experience exponential growth?

young populations with few individuals

Which equation represents the logistic growth rate of a population?

ΔNΔt=rmaxN(K−N)K