Genetics Lecture 6 Flashcards
Define trait.
Characteristic of an individual. May or may not be inheritable.
Define genotype.
Genetic constitution of an individual.
Define phenotype.
Observable trait of an individual.
In addition to the genotype, what else does the phenotype involve (3)?
- Environmental influences
- Random developmental events
- Action of other genes
Define true-breed.
Self-pollinated plants, where all offspring are genetically identical.
Where are genes found?
Each gene has a locus on a specific chromosome.
Define the law of segregation.
Two members of a gene pair segregate from each other during gamete formation in meiosis.
Are heterozygotes true-breeds?
No.
Describe proof for the law of segregation.
Recessive traits, which are masked in the F1 from a cross of 2 true breeds, reappear in a specific proportion in the F2.
Define the principle of independent assortment.
Alleles on different chromosomes are assorted independently of each other.
Define the offspring ratio for a trihybrid cross.
27:9:9:9:3:3:3:1
