Genetics Gregor Mendel Chapter 11
Mendel • Austrian Monk • Was a local high school science teacher • Job was to grow food for the entire monastery • Became interested in how traits are passed from parents to offspring.
Principles of Inheritance • E:\Early_Principles_of_Inheritance.asf
Mendel • Crossed and controlled breeding of pea plants • Used burlap sacks to control pollination of flowering pea plants • Very controlled experiment • Many generations in a short period of time
Mendel’s Work • Crossed a tall pea plant with a tall pea plant, produced all tall plants. • Crossed a short pea plant with a short pea plant, produced all short plants. • Crossed a tall pea plant with a short plant, produced all tall plants. • Took seeds from the previous cross, produced 3 tall plants and one short plant
Monohybrid Crosses • E:\Introduction____Classical_Genetics_and_Monohybrid_Crosses.asf
Mendel’s Research • E:\Gregor_Mendel_s_Research_and_Principles.asf
Mendel’s Discoveries • E:\Mendel_s_Research_and_Discoveries.asf
Mendel’s Hypothesis • Traits are controlled by factors (genes) which always occur in pairs • Factors (genes) separate during the formation of sex cells (gametes). • In a pair of factors (genes) one may mask or hide the effect of the other trait.
Genetic Terms • Homozygous- two alleles that are the same, TT or tt • Heterozygous- two alleles that are opposite, Tt (hybrid) • genotype- using letters to represent traits, TT, Tt, tt. • Phenotype-a physical description of a trait, • Homozygous tall, heterozygous tall.
Genetics • In pigs white coat color is dominant to black coat color. Curly tails are dominant to straight tails. • Cross a heterozygous white coat, heterozygous curly tail male with a heterozygous white coat, heterozygous curly tail female. Predict the possible results.
Probability • E:\Probability.asf
Mendel’s research on Pea Plants • E:\Gregor_Mendel_s_Reseach_on_Pea_Plants_and_His_Development_of_Theories_of_Inheritance.asf
Dihybrid Crosses • E:\Introduction___Dihybrid_Crosses.asf
Breeding Song Birds • E:\Breeding_White_Songbird_Canaries_Through_a_Dihybrid_Cross.asf
Incomplete Dominance • E:\Incomplete_Dominance_in_Snapdragons.asf
Genetics • In four ‘o’ clocks, red is incompletely dominant to white flower color. The heterozygous condition results in pink flowers. • Cross a red flower with a pink flower and predict the results. • Cross a pink flower with a pink flower and predict the results.
Multiple Alleles and Co-dominance • E:\Multiple_Alleles_and_Co_Dominance_in_Human_Blood_Types.asf
Incomplete dominance vs. Co- dominance • Incomplete- you get a mixture. Red and white, you get pink. • Co-dominance- both traits appear. Red and white to make roan. • A and B blood types combine to make AB.
Human Alleles • E:\Possible_Combinations_of_Human_Alleles.asf
Fruit Flies • E:\Research_on_the_Genetic_Make_up_of_the_Fruit_Fly_Drosophila.asf
Sex Linked Inhertiance • E:\Introduction___Sex_Linked_Inheritance.asf
Sex Linked Inhertiance • E:\Inherited_Human_Traits_and_Patterned_Sex_Linked_Inheritance.asf
Color Blindness • E:\Color_Blindness.asf
Hemophylia • E:\Hemophylia.asf
Pedigree Charts • E:\Organizing_Information_About_Sex_Linked_Inheritance_in_Pedigree_Charts.asf