Chapters 17 - 21

Natural Selection, Speciation, Adaptive Radiation, Extinction & Artificial Selection

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. Note that you will lose points if you ask for hints or clues!

1. Natural favours those members of a population best to an environment.

2. Rare mutant forms sometimes enjoy a selective if some biotic or abiotic factor brings about a change in the making it favour their survival at the expense of their competitors.

3. The rapid appearance of bacteria resistant to is an example of high-speed .

4. The frequency of occurrence of a gene in a large population mating at random remains constant unless the gene to which it belongs is affected by , natural selection, gene or genetic drift.

5. The members of a form a natural interbreeding group which is reproductively isolated from other species.

6. The process of speciation depends on to gene exchange dividing a population into two or more groups, each of which takes its own course of evolution.

7. radiation is the over a very long period of time of a group of related organisms along several different lines by each becoming adapted to suit a particular ecological .

8. Evolution is a process. As new species appear, other less successful ones become .

9. Important wild varieties of crop plant and endangered species are often conserved in cell and breed farms.

10. Breeders use selection to selectively breed organisms useful to mankind. Loss of genetic is associated with of domesticated plants and animals.

11. The use of in plant and animal breeding often produces offspring which show hybrid .

12. Genes can be located using gene or by recognising patterns on chromosomes.

13. Using genetic , scientists are able to take genetic material from one species and seal it into the of another species producing an organism which would never have arisen otherwise.

14. Sexual between two species of plant can be overcome by using fusion.