Ch 14 - Non-Mendelian Genetics

linked genes tend to be inherited together more than unlinked genes (which are on separate chromosomes)

recombination frequencies can be used to create genetic maps that show the distance between genes on a chromosomes

• map units - distance between genes is measured in this

autosomes - chromosomes that are not directly involved in sex determinations

sex chromosomes - involved in sex determinations and genes have different inheritance patterns than autosomes

sex-linked genes - genes that are located on sex chromosomes

multiple gene inheritance - these traits wouldn’t follow the ratios predicted by mendelian laws

• ex) more dominant alleles inherited = taller the plant will be

• many different genotypes —> height in the middle of the range

nonnuclear inheritance - genes on the mitochondria or chloroplast DNA don’t follow the inheritance patterns seen in genes located on nuclear DNA

• eggs/ovules are larger —> contribute more mtDNA than sperm/pollen

• ovules contribute more cpDNA than pollen

• traits on nn DNA demonstrate maternal inheritance

phenotype = genotype + environment

• environment could affect gene expression and the resulting phenotype of an organism

• ex) different pH levels affect flower color, exposure to UV light affect melanin

phenotypic plasticity - ability of the same genotypes to produce different phenotypes in response to different environmental factors