Genetics Flashcards
What is an allele?
Alternative types of genes
What is genetics?
The scientific study of heredity
What is a genotype?
The genetic makeup of an organism, visible and non-expressed alleles
What is a phenotype?
The physical traits show in an organisms
What is heterozygous?
When an organism has two different alleles for a given trait/gene
- Having two different alleles for the same trait
What is homozygous dominant?
When an organism has two identical alleles for a trait, this allele is dominant
What is homozygous recessive?
When an organism has two identical alleles for a trait, this allele is recessive.
What is incomplete dominance?
When a blended phenotype is created by one allele not being completely dominant over the other
What are the 4 types of cross diagrams?
- Monohybrid
- Dihybrid
- Test
- Reciprocal
What is the ratio for the combination AaBb x AaBb?
9:3:3:1
What is the dominance % of an offspring if one of its parents had AABB?
(AABB x n)
100% dominant
What is the ratio for AaBb x aabb?
4:4:4:4
What is a test cross?
Taking a dominant organism and finding if its other allele is recessive or dominant by comparing offspring to possible punnet squares
- Compares a dominant organism to a homozygous recessive: (An x aa)
What is a proto-oncogene?
A normal gene that when mutated, becomes an oncogene,
- Regulates the cell cycle
What is an oncogene?
A mutation of the proto-oncogene
What is locus?
The position of a gene in an allele
What are autosomes?
All of the numbered pairs of chromosomes in a karyotype,
- Humans have 22 pairs of autosomes and 1 pair of sex chromosomes
What does dihybrid mean?
The result of two parents breeding with two different traits.
What is a dominant trait?
A trait that becomes a phenotype if there is at least one allele for this trait
What is homozygous?
Having two identical alleles for a given gene on the homologous chromosome
What is hybridization?
Breeding two individuals of two different traits in the hope of a desirable result
What is independent assortment?
The randomness of having an allele is not affected by having another specific allele,
- Every combination of alleles is equally likely to occur
What is the law of segregation?
Genes are spread out equally across gametes so that offspring have an equal chance to have any random selection of alleles
What is monohybrid?
The combinations of alleles possible from two parents when looking at a single trait