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Genetics & Populations, Mendel's priciples - Coggle Diagram

- - - - same with sister chromatids at metaphase II
    - - Gene pairs (not linked) segregate independently
  - - - Phenotype is intermediate in heterozygote
    - - More than two alleles possible at a single locus
      - Example: blood type
    - - Produces two gamete types instead of 4
    - - Phenotype is result of cumulative of many genes
    - - One gene interacts with another
      - Can mask or interfere with expression of other gene
    - - Genes are close together on the same chromosome
      - Crossing over is less likely
    - - Single gene causes multiple effects on the phenotype
    - - Have more than 2 copies of a chromosome
      - Autopolyploid
        
        Failed meiosis
        
        Self fertilization allows to be fertile
      - Allopolyploid
        
        Mating between different species
      - Example: wheat
      - Lots of benefits in plants
        
        Masks negative recessive alleles
        
        Lots of plants we eat are polyploidy because bigger fruit/yield
- - - - No migration
        
        Can be affected by environment
        
        Crop plants to wild plants
      - Large population
        
        If small, genetic drift
        
        Bottleneck effect
        
        Natural diaster causes lots of death
        
        Loss of alleles
      - No mutation
      - Random mating
        
        nonrandom mating
        
        Pollen vectors let choose mates
        
        Some reproduce more than others
        
        Male-male competiton (pollen tubes
        
        Female choice (stigma selects)
      - No selection
        
        Natural selection
        
        One allele is advantage
        
        Artificial selection
        
        Humans pick alleles for benefits
    - - 2pq= genotypic frequency of Rr
      - q2= genotypic frequency of rr
      - p2= genotypic frequency of RR
  - - - Something selects for a certain trait
    - - Intermediate is selected for
    - - baseline
    - - Intermediate is not selected for.
      - Extremes of both ends
- - - - Exponential growth
        
        J shaped
        
        Unlimited resources
        
        dN/dT = rN
        
        R-selected
        
        Annuals
        
        Little investment in defense
        
        Many, small fruit
      - Logistic growth
        
        S shaped
        
        Carrying capactiy
        
        Die off when overshoots
        
        dN/dt = rN(1-N/K)
        
        K-selected
        
        Perennial
        
        Many defenses
        
        Large, few fruits
    - - net reproductive rate (R0)
        
        R0<1, the population size decreases
        
        R0>1, the population size increases.
        
        R0=1, then population size does not change
        
        expected number of offspring an individual will produce over its lifetime in the population
      - Survivorship curves
        
        Type I, typical of K-selected species
        
        Type III, typical of r-selected species
        
        Can change
        
        Can be displayed by same species
        
        Dependent on environment
      - mean generation time (G)
        
        average time between two consecutive generations in the lineage of a cohort
      - intrinsic growth rate (r)
        
        r>0, the population size increases
        
        r<0, the population size decreases
        
        r=1, then population size does not change
  - - - Benefits both
      - Mutualism
      - Pollination
    - - Benefits one, neutral to the other
    - - Negative to one & neutral to other
      - Ex: Black walnut releases chemical to keep other plants from germinating
    - - Both are negatively impacted
      - Competition for resource
    - - Cycles each other
        
        Lotka-Volterra models
        
        dP/dt = faNP-qP
        
        dN/dt = rN-aNP
        
        defintions
        
        dN/dt=rate of change with time of the prey population
        
        r=intrinsic rate of increase for prey
        
        N=number of prey individuals
        
        a=predator’s per capita attack rate
        
        P= number of predator individuals
        
        dP/dt= rate of change with time of predator population
        
        f=constant, indicating predator’s efficiency at converting the prey it has eaten into new predators
        
        q=predator’s per capita mortality rate