Please enable JavaScript.
Coggle requires JavaScript to display documents.
Heredity - Coggle Diagram
Heredity
extensions to Mendel's Principles
Incomplete Dominance
phenotype is heterozygote is intermediate between those of parent homozygotes
multiple alleles
2+ alleles for a particular locus
mutations
changes in genetic makeup of an individual
point mutation; single nucleotide change
chromosome mutation
deletion, duplication, inversion, translocation, transposons
no crossing over
fail to mix alleles across homologs
polygenic inheritance
multiple genes for one character
phenotype; cumulative result of combined effects of many genes
epistasis
one gene interacts with another
may interfere/ mask
linkage
4 haploid genotypes
not produced in equal numbers
pleiotropy
single gene with multiple effects on the phenotype
inheritance of a single gene which visibly
linkage in clarkia
selfer
small petals; flower early; seasonal drought
outcrosser
large petals; flower late; seasonal drought
polyploidy
having more than two copies of a chromosomes
autopolyploid
failed meiosis; self-fertilization
allopolyploid
meiotic error, mismatch during mating; second mating creates matched pairs
evolutionary significance
polyploid mask deleterious recessive alleles
relax selection pressure
accumulate mutations that eventually result in beneficial trait
2 groups of ancient duplications
common ancestor- seed plants/extant angiosperms
genetic variation
diploid individual
has a partner
homologous chromosomes
each homolog from a different parent
independent assortment
metaphase I: orientation of bivalents is random
metaphase II: orientation of sister chromatids is random.
crossing over
happens prophase I
synaptonemal complex forms
mixes the genes present in homologous chromosomes
sexual reproduction
new combination of alleles from each parent
heterozygosity
genetic diversity, bet-hedging, deleterious alleles, cross/ seed pollination
Mendelian Genetics
3 principles
dominance
unique genotype
made of alleles
heterozygosity; 2 genes
homozygosity; same alleles
segregation
separated during meiosis
one allele for each gene
independent assortment
homologs segregate
gene pairs are not linked segregate independently
monohybrid cross
punnett square
dihybrid cross