Mendelian Genetics Flashcards
Allele Versus Locus
An allele is a different form of a gene at a particular locus.
Dominant Traits (uppercase)
Dominant traits are always expressed when the connected allele is dominant, even if only one copy exists
Recessive Trait
expressed only if both the connected alleles are recessive. If one of the alleles is dominant, then the associated characteristic is less likely to manifest
Dominant trait example in humans:
v-shaped hairline
right handedness
Recessive trait example in humans:
Round eyes
Left handedness
Genotype Vs Phenotype
A person’s genotype is their unique sequence of DNA, Phenotype is the observable expression of this genotype
True Bred or Pure Bread Versus Hybrid
Pure Bread consists of gene pairs with genes that are the SAME.
Hybrid consists of gene pairs that are DIFFERENT
Homologous Chromosomes versus Sister Chromatids
sister chromatids are genetically identical, whereas homologous chromosomes are composed of two different chromosomes that are not genetically identical
Gametes versus Somatic cells
Somatic cells contain 46 chromosomes (23 pairs) and gametes contain 23 chromosomes
Haploid versus Diploid
Haploid cells contain only one set of Chromosomes (n). Diploid, contains two sets of chromosomes (2n).
P (sometimes called P0)
refers to the individuals being crossed
F1 (the first filial) refers to
the children of the parents
F2 generation refers to
the generation that is produced by crossbreeding the F1 generation
Principle (Law) of Dominance
when parents with pure, contrasting traits are crossed together, only one form of the trait appears in the next generation
Law of Segregation (Mendel) States
only a single gene copy from a parent is distributed in a gamete, and the allocation of the gene copies is entirely random
