Unit One, Topic 6

Question 1

The process of new species replacing old species in the ecosystem

Answer 1

Succession

Question 2

Biological Control

Answer 2

a method of controlling insect pests using their natural enemies

Question 3

Introduce species

Answer 3

species which are introduced into an environment where they are not naturally found

Question 4

What is the difference between primary and secondary succession

Answer 4

primary succession is the gradual growth of organisms in an area that as previously bare while secondary succession is the gradual growth of organisms in an area that previously had a number of organisms

Question 5

Do plants grow better in burnt soil?

Answer 5

Yes

Question 6

Give an example of biological control of pests

Answer 6

leafy spurge which is a weed that cattle cannot eat and therefore land that has this weed cannot carry livestock

Question 7

An example of an introduced species

Answer 7

black dot spurge beetle

Question 8

What percentage of all things that have lived on earth are now extinct?

Answer 8

90%