HEREDITY

TRAIT

DNA (deoxyribonucleic acid)

• Contains information that forms the hereditary material of all cells.

Chromosome
A single, highly organized and structured piece of DNA.

Gene

• The basic physical and functional unit of heredity made up of DNA.

GENOTYPE

• The exact genetic information carried by a single individual.

PHENOTYPE

• The physical appearance of an organism

DOMINANT TRAIT

• an allele that is always expressed.

RECESSIVE TRAIT

• An allele that is only expressed if there is no other allele present.

ALLELE

• one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome.

PUNNETT SQUARE

• a diagram that is used to predict an outcome of a particular cross or breeding experiment.

HOMOZYGOUS

• Having the same alleles at a one or more gene loci on homologous chromosome segments.

HETEROZYGOUS

• A pair of genes where one is dominant and one is recessive.

PROKARYOTE

• a microscopic single-celled organism that has neither a distinct nucleus with a membrane nor other specialized organelles.

EUKARYOTE

• an organism consisting of a cell or cells in which the genetic material is DNA in the form of chromosomes contained within a distinct nucleus.