Which would be least likely to be affected by a density-dependent limiting factor? A large, dense...

Preview:

Citation preview

Which would be least likely to be affected by a density-dependent

limiting factor?A large, dense population or a small, scattered population

A small, scattered population

Two ways a population can decrease in size?

decreased birthrate and emigration

Suppose that a species of fish is introduced into a new environment in an attempt to reduce the population of

insects. The fish has no natural predators in the new environment.

The fish population would most likely

increase exponentially.

A disease resulting in the deaths of one third of a dense population of bats

in a cave would be

density-dependent limiting factor.

The pattern of spacing between individuals across the range of a

population is its

distribution.

Something that controls the growth or size of a

population is

a limiting factor.

How would you describe a population that is decreasing in size?

The death rate is becoming higher than the birthrate.

The various growth phases through which most populations go are

represented on

a logistic growth curve.

If you know the range of a population, then

you know

the areas that are inhabited by the population.

During some kinds of population growth, the size of each generation of offspring is larger than the generation before it. So, as the population gets larger, it grows more quickly. This

situation is called

exponential growth.

Demography is the scientific study of

human populations.

The movement of organisms into a range is called

immigration.

If the death rate of a population is greater than the birthrate, the

population

decreases

There are 150 Saguaro cactus plants per square kilometer in a 10-square-kilometer area of Arizona

desert. To which population characteristic does this information

refer?

population density

____________ __________limiting factors affect all populations, whether

the population size is two or two hundred.

Density-independent

When you graph a population’s exponential growth over time, you

will have an _________ graph.

J-shaped

___________ growth occurs when a population’s growth slows or stops, following a period of rapid growth.

Logistic

The __________ model of population growth accounts for the influence of

carrying capacity.

logistic

An indication that a country has completed the demographic transition is a ____ birthrate and a _____death

rate.

Low, low

Emigration can cause a population to ____________________ in size.

decrease

Scientists who study human populations and predict the growth rate of the world and of individual

countries study the science of ____________________.

demography

A population of bacteria with an unlimited supply of nutrients will

eventually show ____________________ growth.

exponential

If a population is undergoing logistic growth, it may have a growth rate

near zero once the ____________________ has been

reached.

carrying capacity

Identify 3 limiting factors that depend on population density.

Density-dependent limiting factors become limiting only when the population

density—the number of organisms in a given area—reaches a certain level. These

factors include competition, predation, parasitism, and disease.

Identify 3 limiting factors that do not depend on population density.

Density-independent limiting factors affect all populations in similar ways, regardless of population size. These

limiting factors include weather, natural disasters, and certain human activities,

such as damming rivers and clear-cutting forests.

List the three patterns of distribution.

Random, uniform, clumped

List the four factors that affect population growth.

birth rate

death rate

immigration

emigration

Compare and contrast the graph of exponential growth to the graph of

logistic growth.

The pattern of exponential growth is a J-shaped curve. The pattern of

logistic growth is an S-shaped curve.

What will reduce competition within a species’ population?

Fewer individuals

Recommended