Population Ecology Graphs and Carrying Capacity

Which of the following graphs best represents a population that has reached carrying capacity?

Population Growth

In ecology, a population is defined as a group of organisms of the same species living together in a particular geographic area. Populations grow as new individuals are added. Under ideal conditions, where organisms have unlimited space and resources, populations will continually increase. The growth rate of a population under these conditions is described by the equation G=Rn where GG represents the growth rate of the population, rr represents the per capita rate of increase, and N represents the number of individuals in the population.

Escherichia coli (E.coli) is a bacterial species that is commonly grown in research laboratories. E.coli reproduce by a process called binary fission, where a single bacterial cell divides in two. The two resulting daughter cells are identical to one another and identical to the original parent cell. Under ideal conditions, E.coli will divide every 20 minutes.

But in nature, there are limitations on the growth rates of populations. A number of environmental factors limit population size, such as disease, predators, and drought, and availability of food and suitable habitat. The maximum number of individuals that an ecosystem can support is called the carrying capacity, represented by letter K. The value of K varies, depending on the species and the resources available in a particular ecosystem. The size of a population will generally stabilize once it reaches carrying capacity.

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Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

Which of the following graphs best represents a population that has reached carrying capacity?

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Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

What is the carrying capacity of the graph?

• 1000

• 8000

• 800

• 600

The largest number of individuals that an area can support is called its _______.

• limiting factor

• abiotic factor

• resource availability

• carrying capacity

What is happening at the 'A' on the graph?

• the population overshoots above the carrying capacity

• the population stops growing

• growth begins to slow down due to limited resources

• growth is speeding up due to an abundance of resources

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

Identify the time when this population FIRST reaches the carrying capacity (on the curve and on the axis)

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NGSS.HS-LS2-1

What is the carrying capacity of the graph?

• around 500

• more than 800

• less than 300

• around 700

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

What point on the graph represents the carrying capacity?

• A

• B

• C

• D

Tags

NGSS.MS-LS2-4

The graph to the right shows the interaction of the wolf and moose populations on Isle Pekie. If the moose population continues to increase, the wolves' food supply will increase. What will most likely happen to the wolf population as a result?

• It will decrease.

• It will increase.

• It will remain the same.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

A scientist was studying a population of fish in a pond over a period of 10 years. He observed that

the population increased each year for 3 years, and then remained nearly constant for the rest of

the study. The best explanation for this observation is that the population had

• stopped reproducing

• reached carrying capacity

• mutated into a different species

• run out of food and all died

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4