Exploring Mendelian Genetics. Chapter 11 Section 3 SC B-46: Predict inherited traits by using the principles of Mendelian genetics (including segregation, independent assortment, and types of dominance). Essential Question.
Chapter 11 Section 3
SC B-46: Predict inherited traits by using the principles of Mendelian genetics (including segregation, independent assortment, and types of dominance)
How would you explain the inheritance patterns beyond dominant & recessive?
Mendel also performed an experiment to follow 2 different genes as they passed from parents to offspring
Mendel chose true-breeding round, yellow peas crossed with true-breeding wrinkled, green for F1
(RRYY) x (rryy)
What genotype/phenotype will the offspring have?
The Inheritance of 2 Traits
Does the inheritance of 1 characteristic influence the inheritance of another characteristic?
For example: Does pea shape influence pea color?
Mendel’s plants produced 556 seeds
round & yellow: 315
wrinkled & green: 32
combinations of parent phenotypes: 209
Alleles for seed shape & color segregate independently when gametes forming
Genes from different traits can segregate independently during the formation of gametes.
This accounts for the many genetic variations observed in plants, animals, & other organisms
Inheritance of biological characteristics is determined by individual units called genes. Genes are passed from parents to their offspring.
If there are 2 or more alleles of a gene for a single trait, some forms may be dominant & others recessive
In most sexually reproducing organisms, each individual has 2 copies of a single gene (1 from each parent) & they separate when gametes are formed
Alleles for different genes usually separate independently of one another.
Cases where neither allele is dominant the heterozygous individual will have a phenotype that is a blend of the 2 alleles.
Both alleles for a gene are expressed in the phenotype of a hybrid individual
genes that have >2 alleles
Traits controlled by the interactions of several genes
Genes provide a plan for development but how that plan unfolds also depends on the environment