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