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Heredity - Coggle Diagram

- - - - allele frequency
        
        number of copies of an alele in a population divided by the total number of alleles for that gene in a population
      - genotype frequency
        
        number of individuals iwth particular genotype in a population divided by total number of individual in a population
  - - - look at notes for these examples
  - - - all alleles in population add up to 100% or 1
      - all genotypes in population add up to 100% or 1
      - red and white flower exmaples
        
        allele frequencies r=0.38, R=0.62
        
        0.38+0.62=1
        
        Genotypic frequencies: rr=0.25, RR=0.48, Rr=0.27
        
        0.25+0.48+0.27=1
  - - - RR=0.38, Rr=0.24+0.24=0.48, rr=0.14
      - the frequency of gametes carrying a particular allele is equal to allele frequecny for a population in Hardy Weinerg equilibrium
      - multiplyinhg the allele frequencies gives the proportion of each allele combination in the population
  - - - the freq of dominant allele is repped by p
      - freq of recessive allele is repped by q
      - p+q=1
      - (p+q)^2=1^2
      - p^2+2pq+q^2=1
        
        p^2=genotypic freq of RR
        
        2pq=genotypic freq of Rr
        
        q^2=genotypoc freq of rr
- - - - change in one of nucleic acids, some are apparant in phenotype, source of all new alleles, must be gametes to be inherited. male pollen sperm, female ovule egg
  - - - 2 phenoytpes, dominany recessive systems
  - - - natura catastrophe, migration
  - - - based on individual phenotypes
    - - male-male competition
        
        excess of pollen grains
        
        pollen tubes can interfere with one another
      - female choice
        
        barriers on stigma surface preventing germination
  - - - immigration:into
      - emigration: out of
    - - GMO
      - climate change
      - speciation
  - - - increased frequency of desired trait
      - elimination of undesired traits
- - - - The orientation of bivalents is random
    - - orientation of sister chromatid is random
    - - humans are example, with 46 chromosomes
        
        2^46 =7.04 x10^13
    - - Gene pairs that arent related (homologs) segregate independently
      - gene pairs that arent linked segregate independently
      - evidence from dihybrid cross
        
        3:1 phenotypic ratio for each of the 2 alleles
        
        Dihybrid example:
        
        parental
        
        true breeding
        
        homozygous
        
        F1
        
        First flial
        
        heterzygous
        
        Genotypic ratio
        
        allele combinations
        
        Phenotypic ratio
        
        trait combos
  - - - genetic diversity
      - bet-hedging to novel environments
      - Multiple deleterious alleles can be bunched together and eliminated
      - escape host parasite negative impacts
    - - cross pollination vs self
- - - - J shaped curve
      - unlimited resources
    - - S shaped curve
      - typical of a population that self regulate, has carrying capacity (K)
- - - - each individual has a unique genotype
      - genotype made of alleles
      - phenotype determined by these alleles (and environment)
      - no guarantee that allele will manifest
      - Heterzygosity
        
        one of 2 genes (dominant allele) has a detectable effect on organism's appearance
        
        the other gene has no detectable effect (recessive allele)
      - Homozygosity
        
        both alleles are same
    - - alleles segregated, seperated, from one another during meiosis
      - each gamete has only one allele for each gene
      - offspring inherit 2 alleles for a gene
        
        one from each parent
        
        inherit a homologous chromosome
      - during meiosis, 2 members of gene pair seperate from each other
      - Each gamete has equal chance to inherit either one of gene
  - - - Phenotype of heterozygotes is intermediate between those of parent homozygotes
      - Snap dragons (red x white = pink)
    - - many populations have more than 2 alleles for particular locus
      - punnett square
      - breeding experiments to determine dominance
      - figuring out alleles is complex
    - - changes in genetic makeup of an individual
      - point mutation
        
        single nucleotide changes
      - chromosome mutation
        
        deletion
        
        segments of chromosome lost
        
        duplication
        
        part of chromosome are doubled
        
        inversion
        
        piece rotates 180
        
        translocation
        
        exchange of parts between 2 nonhomologous chromosome
        
        transposons
        
        movable genetic element
        
        jumping genes
    - - fail to mix alleles across homologs
      - chromosome inherited same as parent
      - only 2 gamete types possible rather than 4
    - - multiple genes for on character
      - phenotype is cumulative result of combines effects of many genes
      - exmaple is abscisic acid
      - most traits
      - continuous variatoin
      - populations tend to have normal distribution
    - - one gene intercats w another
      - maye interfere ir mask
      - example is digitalis petal color
        
        one gene impacts red intensity
        
        d light red, D dark red
        
        pigment location: w throughout corolla, W spots of nectar guide
    - - 4 haploid genotypes
      - not made in equal numbers
        
        recombinants less abundant
        
        parentals more abundant
      - Linkage in Clarkia
        
        selfer
        
        small petals, flower early, seasonal drought, physiologically escape
        
        outcrosser
        
        large petals, flower late, seasonal drought, physiologically tolerant?
    - - single gene with multiple effects on the phenotype
      - inheritance of single gene visibly influences several traits
      - example: awn of wheat, wheat with awns have greater yield than those without awns
    - - having more than 2 copies (2n) of a chromosome
      - autopolyploid
        
        failed meiosis
        
        self fertilzation
      - allopolyploid
        
        meiotic error
        
        mismatch during mating
        
        second mating creates matched pairs
      - ex: wheat
        
        result of sequential hybrid doubling & quadroupling
        
        original ancestor species had 14 chromosomes
        
        Durum wheat (28 chromosome, tetraploid, pasta)
        
        Bread wheat (42 chromosome, hexaploid, gluten for lofty bread)
      - Polyploid example:
        
        strawberry, chemically induced
        
        prevent microtubule formation
        
        required for meiosis occur properly
        
        make diploid gametes, during fert 2 diploid gametes fuse, reuslt in tetraploid (4n)
      - Evo Significance
        
        polyploid mask deleterious recessive alleles
        
        relax selection pressure
        
        accumulate mts that eventually result in beneficial trait
        
        2 groups of ancient duplications: common ancestor of seed plants, common ancestor of extant angiopserms