Vocabulary
An animal that captures and eats other animals is called a ________________.
An animal that is captured and eaten is the _________.
Predator
Prey
Since humans can eat foods from many different ecosystems, they are:
part of many food webs.
In a healthy ecosystem, many different kinds of organisms can ____________.
meet their needs.
A natural change to an ecosystem occurs when
a change occurs that do not involve people
True or False:
Humans cause more negative changes to ecosystems than positive.
True
A(n) ________ species is a non-native organism that causes harm to the environment.
invasive
Living things obtain ______ from their environment and release ______ back into it.
matter; waste
Scientists studied the relationship between wolves and moose on Isle Royale. Their study showed that in a healthy ecosystem,
the numbers of predators and their prey must be balanced.
What kinds of changes take place during succession?
A slow replacing of species in the ecosystem. This happens in one direction from few species of small organisms to many organisms of all sizes.
People use resources such as __________, ________, and _________ to generate useful energy.
natural gas, coal and oil
Anything that people add to the environment that harms living things is considered
pollution
What do all food chains have in common?
They all begin with a producer.
If just one species in a food chain disappears,
any organisms that depend on that species for food will not be able to meet their needs.
After a forest fire, new plants and those that were not burned will ______ because the fire released nutrients into the soil.
grow faster
Clearing prairies to plant crops is a negative change to ecosystems because
the way organisms interact in food webs is disrupted.
All the goods and services people need or want are either made of __________ or produced using them.
Natural Resources
Why is the base of an energy pyramid larger than the top?
Energy is lost as heat at each level so less energy is available at the top
On Isle Royale, many wolves died because they had less food. With fewer predators, the number of moose
increased quickly
Climate change can cause changes to ecosystems. What can happen to organisms that do not change with their ecosystems?
They can disappear from Earth.
An example of a disturbance in the ecosystem is:_______________________.
Examples include: a volcano eruption, a drought, a tornado, a forest fire
An event that changes an ecosystem for a long period of time is called a ______________.
Disturbance
How are food webs related to food chains?
Food webs consist of overlapping food chains.
Herons will sometimes stand motionless in their habitat for an hour, waiting to catch their prey. They’ve even been known to swallow turtles whole. What would happen to the herons if the number of turtles decreased in this habitat?
The herons’ food supply would decrease and hurt their survival.
After an ecosystem has been destroyed, it
can usually can be restored.
True or False:
Many changes in an ecosystem occur in cycles.
True (seasons are an example of a change that occurs in a cycle).