Factors (Evidence)

Question 1

Reason for natural selection

Answer 1

not every offspring can survive and reproduce- would cause severe overpopulation
organisms produce more offspring than can survive- competitive environment within the population
better adapted organisms in a population are more likely to survive

Question 2

“fittest offspring”

Answer 2

survive, reproduce, leave offspring

Question 3

extinction

Answer 3

cannot be reversed
species go extinct for many reasons
organisms that don’t survive survival of the fittest

Question 4

genetic variation

Answer 4

‘the variation in physical traits in a population due to inheritance”
variation between all individuals except identical twins

Question 5

genetic drift

Answer 5

“genetic traits change in populations slowly over time dur to chance alone”

Question 6

generations

Answer 6

each new generation consists of a higher percentage of individuals who posses the adaptations that helped their parents to survive
parents pass on traits to offspring that helped them survive

Question 7

mutations

Answer 7

very rare
only way for new genes to be introduced
most appear in parts of DNA that don’t create genes
most cells that have mutations in genes die or become cancerous
cancerous cells are either destroyed by immune system or become tumors
mutation has to happen in sperm or egg
natural selection acts on mutations