Interactions and Interdependence: Balance in an ecosystem

Question 1

True or false:

In an ecosystem, living organisms and the environment that supports them are in a fine balance.

Answer 1

True

Question 2

True or false:

An ecosystem can support any number or organisms no matter how many resources it has.

Answer 2

False.

The number of organisms an ecosystem can support depends on the resources available.

Question 3

Name these 3 resources.

Answer 3

• Food
• Water
• Shelter

Question 4

Fill in the missing words:
In general, if there are plenty of resources, an ecosystem can support ____ individuals and _____ populations. If resources are scare, the numbers of individuals and the size of the populations will be ____.

Answer 4

Many, large, small

Question 5

Fill in the missing words:
If food is in short supply, organisms compete for access to food and only the _____ plants and animals are likely so survive. This will _____ the number of organisms. When there is more food available, the number of organisms will _____, keeping the ecosystem in _____.

Answer 5

Stronger, decrease, increase, balance

Question 6

True or false:

What happens to one population affects the whole community.

Answer 6

True

Question 7

Fill in the missing word:

If an ecosystem does not remain in balance, it will ____.

Answer 7

Fail

Question 8

Name 2 things that can disrupt the balance in an ecosystem.

Answer 8

• Human factors (Pollution)

- Natural factors (Fires, droughts)

Question 9

Fill in the missing words:
If a disruption lasts a short period of time, the ecosystem will _____.
If a disruption lasts a long period of time, or is very severe, damage might be so bad that ecosystem ____ recover.

Answer 9

Recover, can’t

Question 10

Why do people poach?

Answer 10

Some organisms can be exported and sold for thousands of rands.