Mendel and Meiosis

Genetics-- scientific study of heredity

True-Breeding produces offspring identical to themselves if allowed to self pollinate.

Trait characteristic that varies from one individual to another

Hybrid parents have 2 different traits. Heterozygous for a trait.

Gene sequence of DNA codes that determines a trait

Allele one of a number of different forms of a gene

Segregation separation of alleles during gamete formation

Gamete male or female sex cell. Egg or sperm

Probability likelihood that something will happen

Punnett square diagram that shows the gene combinations that might result from a genetic cross.

Homozygous two identical alleles

Heterozygous two different alleles

Phenotype what the trait looks like

Independent assortment genes are inherited seperatly

Incomplete Dominance in heterozygous state the traits(alleles) blend

Co dominance when both alleles show up at same time red and white, not pink

Multiple alleles more than 2 alleles for trait or gene (blood)

traits controlled by 2 or more genes Polygenic traits traits controlled by 2 or more genes Skin color is controlled by 8 genes

Homologous corresponding chromosomes from opposite parents

Diploid cell with double set of chromosomes 2n this is the normal number

Haploid (monoploid)— 1/2 the normal number of chromosomes. 1n 1 set of chromosomes

Meiosis division of primary sex cells to make haploid cells

Tetrad 4 chromosomes hooked together at centromere during meiosis

Crossing over part of 1 chromosome switches places with part of a homologous chromosome.

Gene map map of what the genes look like and what chromosome they are on.