Trait:

A characteristic caused by genetics or the environment

Chromosomes:

Long strands of DNA that contain thousands of genes

Genes:

Part of chromosome that contains a trait(30,000 in humans)

Allele:

Different forms of genes

Recessive Allele:

Only see this trait if two are present

Dominant Allele:

Always shows its trait

Hybrid:

Has two different alleles for same trait

Purebred:

Has two identical alleles for same trait

Probability:

The likelihood that an event will occur

Punnett Square:

A chart that shows all possible combinations of alleles between two organisms

Phenotype:

The visibly expressed trait (ie. blue eyes)

Genotype:

The allele combination for a trait (ie. Bb or bb)

Homozygous:

Two identical alleles (Purebred)

Heterozygous:

Two different alleles (Hybrid)

Codominant Alleles:

Neither allele is dominant(ie. Blood types or spotted dog)

Incomplete Dominance:

The dominant alleles mix - (Green flower from blue and yellow alleles)

Meiosis:

Process that create sex cells with one copy of each gene or half the number of chromosomes

Cross-Fertilization:

A gamete(sex cell) from each parent gives one allele for each trait to make a new organism(humans)

# of human chromosomes:

23 pairs of 46 chromosomes

X and Y:

Human chromosomes that determine gender

Mutation:

When a chromosome is not copied correctly

Carrier:

Someone who has one recessive allele for a trait but doesn't show it

Pedigree:

A chart that tracts a particular trait in one family

Karyotype:

A picture of all the chromosomes of a cell

Genome:

All the DNA in one cell of an organism

Genotype:

An analysis of a genome to determine inherited traits