Patterns of Inheritance Flashcards
Genetic composition.
Genotype
Observable characteristics.
Phenotype
Variations of a gene.
Alleles
Follow a simple pattern of inheritance as defined by Mendel’s laws of dominance. —> Establishes that dominant traits will be expressed over recessive traits.
Autosomal Alleles
Lead to expression of the allele whether the individual has 1 or 2 copies of the allele.
Autosomal Dominant Alleles
Are only expressed when the individual is homozygous for the allele.
Individuals with 1 copy of the recessive trait are carriers and could pass the recessive allele on to future generations.
Autosomal Recessive Alleles
A characteristic pattern of inheritance exhibited by genes located on a sex chromosome (X or Y).
Sex-Linked Alleles
Can give rise to a variety of phenotypes because of gene interactions and interactions between genes and their environment.
Complex/Multifactoral Traits
Organized profile of an organism’s chromosomes.
A way to characterize the chromosomes located in the nucleus of a eukaryotic cell. —> By number, relative size, shape, and appearance of chromosomes.
Karyotype
The identical copies of each chromosome that the centromere joins.
Sister Chromatids
The location where the sister chromatids are closest together.
Centromeres
An image of chromosomes arranged by size (and other characteristics).
Image of chromosomes from a cell.
Karyogram
An organism with the appropriate number of chromosomes for the species.
Euploid
An organism with more or less than the appropriate number of chromosomes for the species.
Aneuploid
To prevent significant impacts of having an “extra” chromosome, one of the X chromosomes is inactivated (in females).
X-Inactivation
Inactive X-chromosome.
Barr Bodies
Family tree.
Pedigree
The 1st identified individual who exhibits an inherited disease or disorder.
Propositus
If 1 or both alleles are mutated, the individual will exhibit the disorder.
Heterozygous individual with the disorder have a 50% chance of passing on the mutated allele.
Homozygous individual with the mutated allele will pass the mutated allele on to EVERY child.
No carriers for a dominant disorder. —> All individuals with a mutated allele will exhibit the disorder.
Autosomal Dominant Disorder
Only indictable who exhibit the disorder have 1 or 2 copies of the recessive allele without a dominant allele to mask it.
ex. Sons inherit only 1 X chromosome (from their mothers) so if a mother exhibits this (indicating that both X chromosomes are affected) then 100% of her sons will inherit a mutated X chromosome and exhibit this because they don’t have another X chromosome to mask it.
Family members with only 1 copy of the recessive allele are said to be carriers.
Sex-Linked Recessive Disorder
A family tree showing which members have the genes for a certain trait.
Pedigree
Traits carried on a chromosome other than X or Y.
Autosomal Traits
Traits that appear on the X or Y chromosome.
Sex-Linked Traits
Trait that is on the X chromosome.
Shows up more often in males because if they inherit 1 X chromosome that has the trait, they are automatically affected while females are only affected if they inherit an X from each parent that carries the allele for the trait.
X-Linked Trait
