Page 48 - Science Course 3 (Book 1)

Mo2-L1a: How Population Changes Affect an Ecosystem?

Population density is the size of a population Extinct Animals
compared to the amount of space available.

A high population density can increase competition
and make it easier for disease to be transmitted
from one individual to another.

There is a limit to resources an ecosystem can provide.
Key Concept
Carrying capacity is the largest number of individuals How Population Changes Affect an Ecosystem?
of one species that an ecosystem can support over
time. How do population changes affects ecosystems?

If a population exceeds its carrying capacity the area
becomes over-populated.

Environment resistance

Decreasing O 2 supply Low food supply Disease Predators Limited space

carrying capacity SUMMARY

Population size How Population Changes Affect an Ecosystem?

Ecosystems are all the living and nonliving
things in a given area.
Populations can increase and decrease.

Time

If all the members of a population die or move away
from an area, that population becomes extinct.

If all populations of a species disappear from Earth,
the entire species becomes extinct.

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