WHAT DOES MEIOSIS HAVE TO DO WITH IT?

REMEMBER _____________ chromosomes ________________ during ANAPHASE I = _________________ SEGREGATION Image modified from: HOMOLOGOUS SEPARATE

Genetic Vocab. You Should Know!!! Genotype – ________ that make up a trait –Ex – AA, Aa, aa Phenotype –__________ appearance –Ex – green, yellow Homozygous – Two alleles that are the _____ –Homozygous dominant: AA –Homozygous recessive: aa Heterozygous – Two alleles that are __________ –Example Aa, aA Genes Physical same different

_________ Squares ____________ cross –Cross involving one trait Gametes go on the top and side Combine gametes to find possible offspring ___________ Ratio –1 TT: 2 Tt: 1tt ___________ Ratio –3 Tall, 1 Short Tt X Tt Punnett Monohybrid Genotype Phenotype

__________ Cross Looks at the inheritance of two traits Mendel determined traits were inherited _____________ of each other This is called the _______ ____ ____________ ____________ Dihybrid independently Law of Independent Assortment

Non-Mendelian Genetics Not all traits follow Mendel’s Law of Dominance Four Variations –Incomplete Dominance (blending) –Codominance (two phenotypes) –Multiple Alleles –Polygenic Traits

Dominance Neither allele is dominant, both produce a protein Heterozygous phenotype is a blend of both homozygous phenotypes Ex- pink flowers; wavy hair Incomplete

Neither allele dominates the other, both produce a protein Heterozygous phenotype is a combination of both homozygous phenotypes because both alleles are equally seen in phenotype Ex – checkered chicken, human blood types, Codominance

Two dominant alleles are expressed at the same time R R WW RW White Red Roan Sickle-Cell Anemia is another Codominant trait.

Alleles Some genes have more than two alleles Each individual only gets two, but there are more than two in the population Ex – Rabbit fur color Multiple

Human Blood Typing as an example of Codominance and Multiple Alleles Blood has 3 alleles, A, B, and O A and B are Codominant over O O is recessive PhenotypeGenotype Can Receive From Can Donate To A B AB O I A I A, I A i I B I B, I B i IAIBIAIB ii A, O B, O A, B, AB, O O AB B, AB A, AB A, B, AB, O

Traits Many traits are controlled by more than one gene Traits show wide variation Ex – human height, IQ, skin color, eye color, bell pepper colors Polygenic

Sex Linked-Traits Traits that are located on the sex chromosome (mainly the X chromosome) Hemophilia: Failure to clot blood and Muscular Distrophy: wasting away of muscles Fathers(XY) can only pass disorders to Daughters (XX). Mothers(XX) can Pass disorders to Both sons(XY) & Daughters(XX). Most disorders are carried on the X chromosome so males are more likely to inherit them.