Lecture 5 Flashcards
What does Consanguinous Mating cause?
A rare disease to turn more common do to increasing the likelihood of homozygotes in a family and decreasing the likelihood of heterozygotes.
What are inbred lines of self-fertilized plants?
Homozygous for alleles that were present in the founding like to make genetically uniform fruits.
What happens when two different inbred lines are crossed?
The hybrids are heterozygous for many genes.
These heterozygotes display heterosis, or hybrid visor.
What is the Hardy Weinberg Principle?
Predicting genotypes through allele frequencies in a population.
What is the Hardy Weinberg Equation?
p2 (Dom Homo) + 2pq (Het.) + q2 (Recessive Homo)
What can make the Hardy Weinberg equation wrong?
- Nonrandom Mating
- Unequal Survival
- Population Subdivision
- Migration
What is Dosage Compensation?
A way of equalizing gene expression in the face of different gene dosage.
When are the X and Y chromosomes homologous?
Only at pseudoautosomal regions. which are essential for X-Y chromosome pairings in meiosis in the male.
What did Mary Lyon propose?
The random inactivation of one female X chromosome, if a cell contains more than 2 X chromosomes, all but one of them are inactive.
What are females?
Functionally hemizygous for X-linked genes at the cellular level (most genes on X chromosomes are for hormonal purposes)
What is the significance with Calico cats?
It is an XX gene, and the orange gene is on the X-chromosome
What are females that are heterozygous for X-linked traits called.
Genetic Mosaics
How is dosage compensation for X-linked genes achieved by?
Inactivating one of the two X chromosomes in females.
What is an example of Mosaics in Humans for X-linked genes?
Colourblindness (On X chromosome)
Females have been reported having colourblindness in one eye meaning they are heterozygous and mosaics.
