Genetics Flashcards
Genetics
Study of biological inheritance
Each gamete only has
one set of chromosomes
Traits =
a specific characteristic of an individual
Mendel’s Experiment
Crossing of two pea plants in order to study genetics
Genes
DNA that determines a trait, passed on from parents to offspring.
Alleles
Forms/Variations of the same gene
Genotype
The two alleles genetic makeup
Phenotype
The traits being expressed
Law of Dominance
Mendel’s Law of Dominance states that when two different alleles for a trait are present, the dominant allele is expressed, while the recessive allele is masked unless both alleles are recessive.
Homozygous Dominant
Both alleles given by mommy and daddy are dominant
Homozygous Recessive
Both alleles given by mommy and daddy are recessive
Heterozygous
One allele is Dominant and one allele is Recessive
Mendelian Genetics
Only if there are two possible outcomes for alleles. Very simple
Non-Mendelian Genetics
If there are blends, combinations, or more than two outcomes.
Dominant Alleles
Dominant Alleles will be expressed if they are present in the genotype
Recessive Alleles
Recessive Alleles will be expressed only if both mom and dad give a recessive allele.
P
Parental generation
F1
First Filial Generation
F2
Second Filial Generation
Monohybrid Cross
One gene is responsible for the trait
Law of Independent Assortment
genes for different traits can segregate independently during the formation of gametes, therefore causing offspring with genetic diversity and not fixed genotypes.
Dihybrid Cross
Two genes are present in the crossing
Incomplete Dominance
One allele is not completely dominant over the recessive: This results in mixed results of the two alleles.
Co-dominance
phenotypes produced by both alleles are clearly expressed. Both dominant and recessive are shown.
Mulitiple Alleles
More than two alleles for one gene
Blood Types are
Multiple Alleles and Codominance
Polygenetic traits
Traits controlled by multiple genes
Sex Linked Inheritance
Inheritance patterns linked to sex chromosomes
Pedigrees
The recorded ancestry of a gene
Autosomal Chromosomes
Chromosomes that are not the X and Y sex chromosomes
Why are there sometimes different patterns of inheritance in males and females?
Because some disorders are coded on sex chromosomes, which varies based off of sex.
X-linked Inheritance
Inheritance of traits on the X sex chromosome
Genes on Y are
passed on from father to son, only on males
In X-linked inheritance in males, men only need ___ in order to express it.
One allele, regardless of dominance or recessiveness, as men only have one X chromosomes.
Therefore, it is statistically more common for who to have x-linked inheritance expressions?
Males
