GVR: Genetic diversity and adaptation Flashcards
Define Genetic Diversity:
The number of different alleles in a population.
Define phenotype:
The expression of a genotype and its interaction with the environment.
How are new alleles produced?
Mutations.
What are the three types of natural selection?
- Stabilising selection
- Directional selection
- Disruptive selection
What is stabilising selection?
- Favours intermediate phenotypes
- Extreme phenotypes are disadvantaged
What is directional selection?
- Favours extreme phenotypes
- Intermediate phenotypes are disadvantaged
Give an example of stabilising selection:
Human birth weight
Give an example of directional selection:
Antibiotic resistance
What is evolution?
A change in the allele type and frequency in a population.
How are new alleles of a gene created?
Mutation of the DNA base sequence.
Define interspecific competition:
When individuals of different species compete for the same resources in an ecosystem.
Define intraspecific competition:
When individuals of the same species compete for resources in an ecosystem.
What is an extremophile?
An organism that can successfully survive and reproduces in extreme environments.
What is an adaptation?
A long-term response by which a species becomes fitted to its environment.
What are the three types of adaptations?
- Anatomical
- Behavioural
- Phisological
Why is adapting to live in harsher climates an advantage?
- Allows organisms to survive in areas where other species cannot.
- Reduces interspecific competition
What are anatomical adaptations?
Adaptations that occur as an internal or external feature.
What are behavioural adaptations?
- Adaptations that impacts the way an organism acts.
- They are either inherited or learnt through experience and observation.
What are physiological adaptations?
Adaptations that impact the processes that occur inside an organism.
Give 3 examples of anatomical adaptations in animals:
- Body coverings
- Camouflage
- Mimicry
Give 3 examples of anatomical adaptations in animals:
- Spines
- Swollen stems
- Waxy cuticle
Give 3 examples of behavioural adaptations in animals:
- Survival
- Courtship
- Seasonal
Give 3 examples of behavioural adaptations in plants:
- Phototropism
- Geotropism
- Carnivorous plants
Give 3 examples of physiological adaptations in animals:
- Poison production
- Homeostasis
- Reflexes
Give 3 examples of physiological adaptations in plants:
- Toxin production
- CAM photosynthesis
- Seed dormancy
What is CAM photosynthesis?
Gas exchange only at night to prevent water loss.
What behavioural adaptations have adapted animals done to survive in cold environments?
They will eat large amounts of high energy foods to help maintain body temperature.
What physical adaptations have adapted animals done to survive in cold environments?
- Streamlined, compact body shape (smaller SA:V)
- Larger SA:V animals will have thick layers of fur (for insulation)
What behavioural adaptations have adapted animals done to survive in hot deserts?
- Spend much of day in water to help loose heat.
- Organisms may be nocturnal so they are most active in cooler temperatures
What physical adaptations have adapted animals done to survive in hot deserts?
- Large ears increase their SA:V, allowing them to loose more heat.
- Kidney structure adaptations (produce less urine to compensate for water loss through evaporation).
