10.1 Flashcards
What makes species different from one another? (1)
The combination of alleles they possess
How can a greater allele frequency in a species help the species adapt to environmental change? (4)
(1) the greater the number of different alleles that all members of a species possess…
(2) the greater the genetic diversity of that species…
(3) as it has a wider range of characteristics
(4) so there’s a greater probability that some individual in that species will possess a specific characteristic that’ll suit it to the new environmental conditions
What are the 3 factors that influence genetic diversity? (3)
(1) selective breeding
(2) the Founder effect
(3) genetic bottlenecks
Describe the process of selective breeding and how it affects genetic diversity (GD). (5)
(1) it involves identifying individuals with desired characteristics in the same species…
(2) and interbreeding them together to produce offsprings with the desired characteristics
(3) this leads to breeding OUT unwanted characteristics from the population
(4) so the variety of alleles in the population is deliberately restricted to a small number of desired alleles.
(5) so this leads to reduced GD
What is the founder effect? How does it affect adaptability? (2+3)
(1) it occurs when a small group of individuals from a population colonize a NEW REGION,
(2) carrying only a limited fraction of the original population’s alleles.
(3) these alleles aren’t representative of the larger population
(4) so the new population that develops from the few colonisers show less genetic diversity than their original population
(5) so they’re less able to adapt to changing conditions
What is a genetic bottleneck? And what effect does it have on the GD? (2+2)
(1) It occurs when a population experiences a dramatic drop in numbers
(2) due to chance events like natural disasters
(3) the few survivors possess a much less variety of alleles than the og population
(4) which leads to reduced genetic diversity
