Memory Biology: Basic Genetics Memory MatchVersion en ligne Memorize key genetics terms by pairing each concept with its definition. par Alicia Pearce A trait that always shows up. DNA code that determines which traits show. Alleles The cell's control center storing instructions. Chromosomes Recessive Dominant Genotype Different forms of a gene. Threads inside a cell carrying genes. Visible features you can see. Nucleus Phenotype Heredity The passing of traits from parents to offspring. Hidden when the dominant trait is present.