DNA Flashcards
Chromatids (sister chromatids)
Two strands of DNA that make up a duplicated chromosome
Centromere
Region where two sister chromatids attach
Homologous chromosomes
A pair of chromosomes (one from each parent) where each has the same set of genes in the same sequence
Alleles
Different/alternative forms of a gene
Gene
Region of DNA that codes for the amino acid sequence in a protein
Gene locus
The position of a gene on a specific chromosomes (at each gene locus, can only be one allele) “
Homozygous
Identical alleles of homologous chromosomes
Heterozygous
Different alleles on homologous chromosomes
Chromosome
A highly coiled, linear strand of DNA and associated proteins (his tones)
Genotype
The alleles that an organism has
Phenotype
The characteristics displayed by an organism
Recessive
An allele whose characteristics only appears in the phenotype if two copies are present
Dominant
An allele who’s characteristic appears in the phenotype if there’s at least one copy
Incomplete dominance
When the trait from a dominant allele isn’t completely shown over the trait produced by the recessive allele and both alleles influence the phenotype
Multi factorial traits
Characteristics affected by several genetic and environmental factors
