Mendelian Genetics Using Dihybrid crosses 6F predict possible outcomes of various genetic combinations such as monohybrid crosses, dihybrid crosses and non-Mendelian inheritance;

Introduction to Genetics

Warm up activity Answer the following question in your journal. You must have at least 5 complete sentences. What traits do you share with your parents and/or siblings?

Vocabulary Activity Using your iPad, complete your graphic organizer by scanning each of the QR codes around the room.

I. Gregor Mendel (1822-1884) Austrian monk Studied the traits of pea plants “Father” of modern genetics

More Vocab Hybrids-The offspring of crosses between parents with different traits Genes – sequence of DNA that codes for a protein and thus determine traits Alleles – One of a number of a different forms of a gene dominant allele : An allele that expresses its phenotypic effect even when heterozygous with a recessive allele Recessive allele :an allele that produces its characteristic phenotype only when its paired allele is identical

Mendel’s Experiment The hybrids (F1 gen.) only displayed one of the parental traits. (tall) So Gregor wondered why didn’t any of the hybrids come out short??????

When crossing two hybrids, some of the resulting offspring (F2 gen When crossing two hybrids, some of the resulting offspring (F2 gen.) displayed tall, and one displayed short. Traits are encoded on genes???

Alleles – One of a number of a different forms of a gene dominant allele : An allele that expresses its phenotypic effect even when heterozygous with a recessive allele Recessive allele :an allele that produces its characteristic phenotype only when its paired allele is identical

Dominant vs. Recessive Dominant= T Recessive = t

Homo - Same Hetero - Opposite Pheno – Physical Geno - Genetic Allele Types Homo - Same Hetero - Opposite Pheno – Physical Geno - Genetic

Allele Types Definitions Homozygous  Organisms that have two identical alleles for a particular trait (TT or tt) Heterozygous  Organisms that have two different alleles for same trait (Tt) Phenotype Physical characteristic of an organism (tall , round, short, wrinkled, etc) Genotype Genetic makeup of an organism (Tt, tt, TT )

Probability The likelihood that a particular event will occur,

Punnett Squares Punnett squares can be used to predict and compare the genetic variations that will result from a cross.

Punnett Square Complete the Punnett square to show the possible gene combinations for the F2 offspring.

Aha! and Huh? Write down 1 or 2 “ahas” (something you learned) and 1 or 2 “huhs” (things you still have questions about) (have them share with elbow partners)

APPLICATION of GENETIC VOCABULARY

Either use whiteboard or iPad to answer the following: Identify the following as genotypes or phenotypes:

Genotypes or Phenotypes Tt green bb 3 toes

Homozygous or heterozygous Describe as: Homozygous or heterozygous Dominant or recessive

gg CC Dd tt Jj EE

Predict the phenotype if brown (B) is dominate to blue. BB bb Bb

Give the genotypes for the following using ‘A’ as the dominate allele and ‘a’ as the recessive allele: Homozygous dominant Homozygous Heterozygous Recessive Hybrid Homozygous recessive Dominant

Dihybrid Crosses-Interactive lesson Mechanisms of Genetics II 6F (2 of 5) Punnett Squares

Dihybrid Cross Practice Each student will get a template and dry erase marker Complete the cross List all the possible genotypes and phenotypes Write out all the possible phenotypes in words Apply to practice MC question

Example 9/16=56.25% 3/16=18.75% 1/16=6.25%

EOC Biology 2015