Week 14 - Population Biology and Community Interactions

Exponential growth

A constantly accelerating increase in population size that occurs when the size of the population does not affect the growth rate. In nature exponential growth occurs only when populations are well below carrying capacity.

per capita rate of increase (r)

The growth rate of a population expressed per individual. It is calculated as the per capita birth rate minus the per capita death rate.

Which of the following factors does not contribute to environmental resistance? competition for food birth rate competition for space likelihood of contracting a disease from others in population

Birth rate

Which processes increase a population's size? Which processes increase a population's size? Births and deaths. Births and immigration. Deaths and immigration. Deaths and emigration.

Births and immigration.

Which equation represents the logistic growth rate of a population?

ΔNΔt=rMmaxN (K−N)/K

Which of the following statements are true of logistic growth? As the population approaches carrying capacity, it grows more slowly. As the population approaches carrying capacity, it grows more rapidly. When the population reaches carrying capacity, it stops growing. The population grows at a steady rate.

As the population approaches carrying capacity, it grows more slowly. When the population reaches carrying capacity, it stops growing.

Which of the following statements about density-independent growth is true? A population that is experiencing density-independent growth levels off at the environment's carrying capacity. Density-independent growth is also known as exponential growth. The per-capita rate of increase may exceed rmax during density-independent growth. Density-independent growth can continue indefinitely in nature.

Density-independent growth is also known as exponential growth.

Which of the three graphs shown in Part G best represents the growth of these yeast population?

Graph A

Which of the three graphs shown in Part G best represents the growth of this coyote population?

Graph B

Which graph best represents the growth of the beetle population in the sack of corn meal?

Graph C

Which of the following statements about a population experiencing logistic growth is true? Which of the following statements about a population experiencing logistic growth is true? If the K and N values are similar, the amount of available resources is high. If N is less than K, the population will not grow. If the K and N values are far apart, the population will grow very slowly. If N is greater than K, the population will shrink

If N is greater than K, the population will shrink

As a population approaches carrying capacity, environmental resistance __________.

Increases.

What does the orange graph line represent?

Logistic growth

Which factor does not affect a habitat's carrying capacity? Number of nesting sites. Availability of food. Maximum number of individuals in a population. Intensity of predation.

Maximum number of individuals in a population.

What does the right y-axis represent?

Resources, with quantity decreasing from bottom to top.

Carrying capacity

The maximum number of individuals that can be supported in a particular habitat over a sustained period of time.

Which of the following statements are true of a population at carrying capacity? The rate at which resources are used is equal to the rate at which they are supplied. The birth rate equals the death rate. The population growth rate equals zero. The population continues to grow at a constant rate

The rate at which resources are used is equal to the rate at which they are supplied. The birth rate equals the death rate. The population growth rate equals zero.

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

Under which of the following conditions would a population most likely experience exponential growth? Environment with a low carrying capacity. Habitat with limited resources. Large number of individuals in the starting population. Young populations with few individuals

Young populations with few individuals.

One approach to slowing the growth rate is to ?

reduce the birth rate.