Biology 102 Chapter 7
Content
Biology 102 Chapter 7
Why do off springs resemble their parents? *Heredity- The passing of characteristics from parent to offspring through their genes *Selective Breeding- breed for the characterstics that they want.. (Cattle… BIG) *Single Gene trait - Traits that are determined by the instructions a person at one gene. –9,000 human traits are determined by a single gene *Gregor Mendel- Monk/ Father of genetics -Learned about Heredity by conducting expermints in the mid 1800’s -Key to Mendels success was .. Flower color, Pea shape, Pea Color *True Breeding- Dominant and Recessive Traits * Segregation: You’ve got two copies of each gene but put only one copy in each sperm or egg *Dominant trait- Masks the effect of the recessive trait *3 ideas mendal used for explaining this pattern of inheritance 1) Each parent puts into every sperm or egg it makes, a single set of instructions for building the trait,(gene) 2) Offspring thus find themselves with 2 copies of the instructions for any trait (Alleles) 3) The actual trait produced by an individual depends on the two copies of the gene that they inherit from their parents Homozygous- Same & Heterozygous- Different *Phenotypes cant determine Genotypes *Phenotype- The outward appearance of an individual *Genotype- Underlying the Phenotype/ Genetic make up *How do we analyze and predict the outcome of crosses? - Assign symbols to represent different variants of a gene - Generally we use an uppercase letter for the dominant and lower case for recessive *Homozygous dominant AA *Heterozygous Aa * Probability and chance play central roles in genetics Probability has a central role in genetics for 2 reasons -1 Consequence of segregation -2 fertilization is a chance event *Test Cross- Allows us to figure out which alleles an individual carries *Pedigree- A type of family tree used to decipher and predict the inheritance patterns of genes * Incomplete dominance- the heterozygote appears to be intermediate between the two homozygotes *Codominance- hererozygote displays characteristics of both homozygotes
* Blood types- A, B, AB, O - A & B are both dominant to O - A & B alleles are codominant to eachother *Universal donors- O *Universal acceptors- AB * Men are more color blind than women- sex linked trait *Linked genes: Genes on the same chromosome, maybe even right next to each other. * Mendel’s law of independent assortment- Most traits are passed on as independent features:
Why do off springs resemble their parents? *Heredity- The passing of characteristics from parent to offspring through their genes *Selective Breeding- breed for the characterstics that they want.. (Cattle… BIG) *Single Gene trait - Traits that are determined by the instructions a person at one gene. –9,000 human traits are determined by a single gene *Gregor Mendel- Monk/ Father of genetics -Learned about Heredity by conducting expermints in the mid 1800’s -Key to Mendels success was .. Flower color, Pea shape, Pea Color *True Breeding- Dominant and Recessive Traits * Segregation: You’ve got two copies of each gene but put only one copy in each sperm or egg *Dominant trait- Masks the effect of the recessive trait *3 ideas mendal used for explaining this pattern of inheritance 1) Each parent puts into every sperm or egg it makes, a single set of instructions for building the trait,(gene) 2) Offspring thus find themselves with 2 copies of the instructions for any trait (Alleles) 3) The actual trait produced by an individual depends on the two copies of the gene that they inherit from their parents Homozygous- Same & Heterozygous- Different *Phenotypes cant determine Genotypes *Phenotype- The outward appearance of an individual *Genotype- Underlying the Phenotype/ Genetic make up *How do we analyze and predict the outcome of crosses? - Assign symbols to represent different variants of a gene - Generally we use an uppercase letter for the dominant and lower case for recessive *Homozygous dominant AA *Heterozygous Aa * Probability and chance play central roles in genetics Probability has a central role in genetics for 2 reasons -1 Consequence of segregation -2 fertilization is a chance event *Test Cross- Allows us to figure out which alleles an individual carries *Pedigree- A type of family tree used to decipher and predict the inheritance patterns of genes * Incomplete dominance- the heterozygote appears to be intermediate between the two homozygotes *Codominance- hererozygote displays characteristics of both homozygotes
* Blood types- A, B, AB, O - A & B are both dominant to O - A & B alleles are codominant to eachother *Universal donors- O *Universal acceptors- AB * Men are more color blind than women- sex linked trait *Linked genes: Genes on the same chromosome, maybe even right next to each other. * Mendel’s law of independent assortment- Most traits are passed on as independent features:
