Bio 2 Population Ecology 2

True or false: Density dependent factors can affect death rates but not birth rates.

-False

________________ growth is population growth that slows as it approaches the carrying capacity.

-logisitic

Choose two examples of populations that might exhibit the Allee effect.

-A sparsley distributed population, in which individuals have difficulty finding mates -A population of a species that relies on large groups to deter predators

Which of the following describe what happens to a population as it approaches its carrying capacity?

-As a population approaches carrying capacity, resources are used up and growth rate declines

Which of the following accurately defines density-independent mortality factors

-Factors for which mortality remains unchanged in response to population density

Which of the following assumptions would be made when modeling exponential growth?

-Food is plentiful -space is available -water is unlimited

Select all of the following that are density-independent factors that influence population size.

-Hard freeze -fire

What does rN represent in the logistic growth model?

-Intrinsic rate of increase

K-selected species would include which of the following?

-Polar bears -panther -oak trees

What is exponential growth?

-Rapid growth with an intrinsic rate of increase

What are r-selected species?

-Species with high rate of per capita population growth, but poor competitive ability.

Mortality factors whose influence is not affected by changes in number of individuals per unit are called density-_____________ factors.

-independent

Which of the following best describes the result of unchecked exponential growth?

-population explosion

____________- selected species are those with unstable populations that have a high rate of per capita population growth.

-r

The carrying capacity is defined as...

-the maximum number of individuals an environment can sustain

When a population's size does not change over time, the population's growth rate is _______.

-zero

Which of the following accurately describe the following features of a typical K-selected species? A. Life span B. Mortality Rate C. Size of offspring

A.Long B. Usually low C. Large

Place different characteristics of r- and K-selected species in the respective category.

K-selected -long life span -many reproductions per lifetime -extensive parental care r-selected species -short life span -early age at first reproduction -offspring or eggs typically small