Agenda Lab Quiz #9 Turn in Microworlds DO NOT TURN IN PRE-LAB YET!! We’ll go over it.

Punnett Square p P P p PP Pp Pp pp Shows possible combinations of alleles Demonstrates Mendel’s Laws Purple flower allele: P White flower allele: p p P P p PP Pp Pp pp

Punnett Square Problems Heterozygous x white Homozygous yellow (Y) x homozygous green (y)

When it’s not so simple INCOMPLETE DOMINANCE: heterozygotes have a unique or intermediate phenotype

When it’s not so simple INCOMPLETE DOMINANCE: heterozygotes have a unique or intermediate phenotype HH Homozygous for ability to make LDL receptors Genotypes: Hh Heterozygous Phenotypes: LDL receptor Cell Normal Mild disease Severe disease hh for inability to make

When it’s not so simple RR = red hair rr = white hair CODOMINANCE: both alleles are expressed equally in the phenotype of a heterozygote RR = red hair rr = white hair Rr = red hairs and white hairs

Codominant Alleles - Bloodtype Three alleles for blood type A B O This allele is for a protein (blood antigen) on the outer surface of red blood cells

Codominant Alleles - Bloodtype ANTIGENS ANTIBODIES A gene  A protein B gene  B protein O gene  no protein Your body produces antibodies to any protein that you don’t have the gene for

Codominant Alleles - Bloodtype

Blood Type & Multiple Alleles

Sex Linkage Sex Chromosomes = X and Y What do you notice about the X and the Y chromosomes? X chromosome has many genes Y chromosome has few

Sex Linkage Female = ? Male = ? X X X Y

Riddle me this… Xh XH Y XHXH XHY XhY XHXh Hemophilia is a recessive sex-linked disease. Are boys or girls more likely to suffer from hemophilia? WHY? XH Xh Y XHXH XHY XhY XHXh