Genetic Diversity and Adaptation Flashcards
What is genetic diversity
It’s described as the total number of different alleles in a population
What’s a population
A group of individuals of the same species that live in the same place and can interbreed
If the diversity is greater, is there a better or lower chance of some individuals surviving an environmental change. Why?
Better chance of surviving
As there is a wider range of alleles and therefore a wider range of characteristics
In terms of Alleles, when is genetic diversity reduced
When a species has fewer different alleles
Why are not all alleles of a population equally likely to be passed to the next generation
As only certain individuals are reproductively successful and so pass on their alleles
How does reproductive success of individuals affect allele frequency in populations
In a population there will be a gene pool ( the total number of alleles in a particular population at a specific time) containing a wide variety of alleles
Random mutation of allele in a gene pool may result in a new allele ( most cases harmful)
In certain environments, the new allele or a gene might give its possessor an advantage over other individuals in a population
These individuals will be better adapted and therefore more likely to survive in their competition with others
More likely to obtain available resources and so grow more rapidly and live longer. They will have a better chance of breeding successfully and producing offspring
Only those that reproduce successfully will pass on their alleles to the next generation
So as this is an advantageous allele it is most likely to be passed on to the next generation. So are more likely to survive and reproduce.
Over generations, number of individuals with the new advantageous allele will increase at the expense of the individuals with the less advantageous allele
Over time frequency of advantageous allele in population increases and other decreases
