Genetics Vocabulary

Mendel Carried out first important studies of heredity. He discovered: Inherited characteristics are traits using pea plants

Genetics Today-genetics

DNA Deoxyribonucleic acid- DNA Molecule that stores information Blueprint of how your cells need to grow, divide, and function. 1950’s- Great race to discover DNA DNA- described by Francis Crick and James Watson. Images of DNA- Rosalind Franklin and Maurice Wilkins.

Chromosome A structure in the nucleus that contains your genetic information (DNA) Genes reside on your chromosomes Explore:Chromosome

Gene Physical and functional unit of heredity Specific segment of DNA Explores:Genes

Allele An alternative form of a gene. You receive one allele from each of your parents. Interact in a dominant or recessive manner

Heredity Passing of traits from parents to offspring Inheritance of traits Explore: Heredity- Tutorial Inheritance video-http://learn.genetics.utah.edu/content/basics/inheritance/

Trait A trait is a unique feature or quality in a person. Traits are passed down through generations Exploring traits: Traits Tutorial Traits Video: http://learn.genetics.utah.edu/content/basics/traits/

Dominant trait An allele that is always observed even when other alleles are present. Represented by a CAPITAL LETTER RR

Recessive Trait Recessive alleles are only observed when two recessive alleles are present. Represented by lower case letters rr

Heterozygous Organism has two different alleles for a particular gene. Aa

Homozygous When an organism has two identical alleles of a particular gene. aa or AA

Recessive Describing a genetic trait that is not expressed in heterozygotes Aa Tt

Phenotype vs. Genotype Phenotype- the physical characteristic or trait you observe Eye color Widows peak Genotype- is the gene located on the chromosome that codes for the trait or phenotype

Homozygous vs. heterozygous Different alleles Has 1 dominant and 1 recessive allele in the genotype Rr, Aa, Cc. Homozygous Same alleles RR, rr, AA or aa