How are ecosystems balanced?
When are animals able to survive?
When all their needs are met by the environment.
Parasites ____ the host and ____ itself.
hurt, help
A natural disaster can cause an ecosystem to
change quickly
How can people disturb the balance of the ecosystem?
Build houses or throw garbage anywhere
Competition
When two or more species in an ecosystem must use the same limited resources
What is a balanced ecosystem?
What is an example of a parasite?
Tick
Give 3 examples of a natural disaster
earthquake, wild fire, tsunami
What does endangered mean?
A species whose population has been reduced to such small numbers that it is in danger of becoming extinct.
Parasite
an organism that lives on or in another organism, helping itself but hurting the host
An ecosystem has too many chipmunks. What would help balance this ecosystem?
more hawks to eat the chipmunks
What happens to a parasite if a host were to die?
The parasite would either die or leave and find another host.
What is succession?
Gradual change from one community of organisms to another
Why did the United states establish national parks?
to preserve areas and habitats from human destruction
Host
an organism that is harmed by a parasite
If many prey of an animal dies, the number of that predator may_____
decrease
Name two animals in competition
a fox and a wolf
What is one reason animals may become extinct?
Their habitat has been destroyed
What can be done to change damaged areas from strip mines?
Mining companies can replace the soil and have a plan.
hazardous waste
substances that are very harmful to humans and other organisms
plants make___ for animals to use
oxygen
Why aren't a Hawk and an Owl in competition?
A hawk hunts during the day and An owl hunts during the night.
What is a positive outcome of a flood?
population of some fish grow because they use flooded areas to reproduce
How can we help change the environment?
Reduce, Reuse, & Recycle
Extinct
no longer living, as an entire species, or no longer active, as a volcano