Do Now- True for False if false, correct the statement. 1. Certain acquired characteristics, such as mechanical or mathematical skill may be inherited. 2. Certain thoughts or experiences of a mother mark or alter the hereditary makeup of an unborn child. 3. Color blindness is more common in males than in females. 4. A person may transmit characteristics to offspring which he/she does not show. 5. Certain inherited traits may be altered by the stars, planets or moon early in development. 6. The total number of male births exceeds female births each year.

Genetics Chapter 10.2, 10.3, 11.1, and 11.2

1866 Gregor Mendel “Father of Genetics” Austrian Monk that studied pea plants Pure breeds Self Fertilization Statistician who wanted to be a teacher Discovered how traits were inherited in a population

How Genetics Began The passing of traits to the next generation - inheritance or heredity. Mendel performed cross-pollination in pea plants. Mendel followed various traits in the pea plants he bred.

7 Traits Mendel Studied

Mendel studied seven different traits. Seed or pea color Flower color Seed pod color Seed shape or texture Seed pod shape Stem length Flower position

Mendel’s Crosses P Generation: F1 Generation: F2 Generation:

Generations P Generation – the parent generation Parents Pure F1 Generation – the offspring or generation produced by the P Generation Hybrid – 2 different types of genes for a trait F2 Generation – the offspring or generation produced by the F1 Generation 3:1–Yellow : Green

Definitions Genetics: Gene: Allele: Study of hereditary Strand of DNA that codes for a protein (Trait) Allele: A version of a gene

Phenotype vs. Genotype Phenotype: Genotype: Physical characteristics (What the individual looks like) Ex) Red Petals Genotype: Alleles Received (genes you have) Ex) RR

Homozygous and Heterozygous Having two of the same alleles for a particular trait Heterozygous: Having two different alleles for a particular trait

Dominant Vs. Recessive Dominant gene is represented by a capital letter Example - T Recessive gene is represented by a lower case letter Example - t Dominant hides the recessive trait in the heterozygous genotype Example – T=Tall and t=short A person with the genotype Tt would be Tall but they would also carry the short gene to pass on to offspring.

Think – Pair - Share If Fred Flintstone is heterozygous for black hair. (B=Black, b=blonde) What is Fred’s genotype? What is Fred’s phenotype? Tweety bird is yy. (Y= yellow feathers, y=brown feathers) 1. What is his genotype? 2. What is his phenotype? 3. Is he heterozygous or homozygous? Explain.

r R R r Mendels 3 Laws 1. Law of Segregation Each allele a person has separates into different gametes Ex. Rr – one R goes in one sperm and the other r goes into another sperm r R r R Sperm

Mendels 3 Laws 2. Law of Independent Assortment Gene pairs (homologous) will separate randomly into gametes

Mendels 3 Laws 3. Law of Dominance Traits exist in two possible forms (dominant and recessive) The dominant forms hides the recessive trait in the heterozygous condition

Genotypic vs. Phenotypic Ratios Phenotype Ratio: Ratio of different physical traits Ex) Brown eyes ¼ or 25% Genotype Ratio: Ratio of the different possible alleles Ex) Tt = ¼ or 25%

Monohybrid Cross R= Can roll your tongue r= Can’t roll your tongue Genotype Ratio: RR = 1:3 or 25% Rr = 2:2 or 50% Rr = 1:3 or 25 % Phenotype Ratio: Can roll tongue = 3:1 or 75% Cant roll tongue = 1:3 or 25% R r RR Rr Rr rr