Topic4 Genetic Diversity And Adaptations Flashcards
What is an Allele?
Variation of a gene
What is the definition of Genetic Diversity?
What does Genetic Diversity enable?
Genetic Diversity is the number of different alleles in a population
Genetic Diversity enables natural selection
What is the definition of Natural Selection?
Natural selection is populations of living organisms adapt and change.
How does Natural Selection work?
[4steps]
1.Random Mutation which changes DNA base sequence resulting in new alleles of a gene
2.In new environment new alleles is advantageous so possessor more likely to survive and reproduce
3.Advantageous alleles inherited by offspring
4.Over many generations new alleles increase in frequency in population so new alleles become common
What are the different ways adaptations can be?
What are the meanings?
Adaptations can be Anatomical or physiological or behavioural.
Anatomical is spikes on hedgehogs
Behavioural is rolling up in danger in hedgehogs
What is directional Selections?
What is the curve in Directional Selection?
Directional selections favours extreme phenotype
The curve is Directional Selection Curve shifts in direction of phenotype
What is Stabilising Selection?
What is the curve in Stabilising Selection?
Stabilising selection average phenotype has the advantage so variation trait decreases over generation.
Stabilising curve narrows to middle.
Give example of stabilising selection
Human Birth Weight
1.Average birth weight has the Selective Advantage so decrease the possibility of health complications
So
2.Average birthweight more likely to survive and reproduce to pass on their alleles to their offspring
Give example of Directional selection
Antibiotic Resistance in Bacteria
1.Random mutation creates resistance allele in bacterial populations.
2.When exposed to antibiotic those with resistant allele survive and reproduce.
3.Resistance Allele frequency increase over generations
What is the definition of Species?
Similar organisms that can reproduce to produce fertile offspring.
Why might an animal be infertile?
Animals which are infertile is due to chromosome number differences.
What is courtship behaviour?
What three properties of courtship behaviour?
Courtship behaviour increase mating success and survival:
1.courtship behaviour is displayed when sexually mature and fertile
2.courtship ritual make sure organism for a pair bond
3.Allows female to select a strong healthy male.
How does the 3 properties of courtship behaviour increase mating success and survival offspring?
1.When courtship behaviour is displayed this increase a high chance of fertilisation of sperm and egg
2.pair bond means more successful upbringing of then offspring
3.When females select strong healthy male this links to natural selection as advantageous characteristics passed on to offspring.
What is the phylogenetic classification system?
What is it based on?
Phylogenetic classification system is the arrange species into groups based on Evolutionary origins and relationships.
Based on principle all organisms evolved from shared common ancestor
What does Hierarchies definition?
What does taxon mean?
Hierarchies is the smaller groups placed in larger groups with no overlap in between
Taxon is the group.
