Genetic Diversity and Adaptation Flashcards
What is genetic diversity?
The degree of variation in the genes that exist in a certain population
What is an allele?
A different version of a gene
How can genetic diversity be increased within a population?
- Mutations
- Gene flow (migration)
What is natural selection?
A process that increases the frequency of advantageous alleles within a population
What are mutations?
Random changes within a DNA sequence
What is evolution?
The change in allele frequency over time
What is a selection pressure?
An external factor that influences the reproductive success of an individual
What is stabilising selection?
- Where natural selection favours an average phenotype
- In a place where the environment does not change
What is directional selection?
- Natural selection favours one extreme phenotype
- Takes place after an environment has experienced change
What is a genetic bottleneck?
An event that causes a big reduction in the number of different alleles in a population eg, people dying before reproducing
What is the founder effect?
When a few organisms from a population leave to form a new population, so there are only a few different alleles in the gene pool
Steps to RP 6 - Aseptic
- Use a sterile pipette when transferring bacteria to agar plate & spread using a sterile plastic spreader
- Use sterile forceps to place the paper discs with different antibiotics & one soaked in water
- Lightly tape the lid, invert & incubate the plate at 25℃ for 48 hours
- Measure the inhibition/ clear zone to find out efficacy
Why do you have to use aseptic techniques?
To prevent cross contamination.
What are the aseptic techniques?
- Disinfect work surface
- Sterilise equipment, and after use place in disinfectant
- Flame bottle neck of liquid broth
