Mendelian Genetics Part 1 AP Biology Mendelian Genetics Part 1

Gene expression

Gregor Mendel

Character and Trait

Alleles for a gene

One from EACH parent Sperm AND Egg

True breeds & Hybrids

Phenotype vs. Genotype Physical Trait vs. Gene allele type

Test Cross Dominant phenotype, unknown genotype: PP or Pp? Recessive phenotype, known genotype: pp If PP, then all offspring purple: If Pp, then 1 2 offspring purple and 1 2 offspring white: p p p p P P Pp Pp Pp Pp P P Pp Pp pp pp

Monohybrid

Dihybrid

Law of Segregation - Anaphase

Independent Assortment Key Maternal set of chromosomes Possibility 1 Possibility 2 Paternal set of chromosomes Two equally probable arrangements of chromosomes at metaphase I Metaphase II Daughter cells Combination 1 Combination 2 Combination 3 Combination 4

Chance has NO memory.