10.8 Changing population characteristics

Question 1

the process of natural selection

Answer 1

1. organisms of a species have genetic variation and are exposed to selection pressures eg. predation, competition, disease
2. organisms with the best well adapted characteristics will survive and reproduce and those least well adapted will die and not reproduce
3. surviving organisms pass advantageous alleles and characteristics to offspring
4. this process is repeated for many generations, increasing the proportion of organisms with the advantageous characteristics

Question 2

4 examples of modern evolution

Answer 2

anti-biotic resistant bacteria
peppered moths
sheep blowflies
flavobacterium

Question 3

how did the peppered moths evolve during the industrial revolution

Answer 3

before the ID lighter peppered moths had the advantage as they could blend with the light trees
but during the ID the trees were covered with soot so the darker moths had the advantage

Question 4

how did sheep blow flies evolve after a pesticide was developed to kill them

Answer 4

they developed a high resistance to the pesticide this trait was then passed on

Question 5

why did flavobacterium evolve due to opertunity

Answer 5

they evolved to feed on nylon as there was lots available due to the production of and waste of in the factories

Question 6

whats the founder effect

Answer 6

when a few individuals of a species colonise a new area, their offspring initially experience a loss in genetic variation often resulting in individuals that are physically and genetically different from their source population