| A | B |
|---|
| genotype | an organism's genetic makeup or allele combinations |
| phentotype | physical appearance of visible trait |
| heterozygous | an organism that has two different alleles for a trait |
| homozygous | an organism that has two identical alleles for a trait |
| hybrid | Tt, Dd |
| purebred | offspring of many generations that have the same traits |
| Punnett square | a chart that shows all the possible combinatoins of alleles that can result from a genetic cross |
| probability | number that describes the likelihood an event will occur |
| dominant | allele or gene whose trait always shows up in the organism when the allele is present |
| recessive | allele or gene is hidden whenever the dominant allele is present |
| allele | different forms of a gene; an organism's traits are controlled by the alleles from its parents |
| codominance | alleles are neither dominant nor recessive; offspring expresses both alleles |
| gene | DNA that controls for a specific trait |
| DNA | substance of which chromosomes are made |
| heredity | passing on of certain characteristics from parents to children |
| traits | characteristics that affect the way a person looks and acts |
| chromosome | directions for inherited traits on long strands of matter |
| sex-linked trait | genes for these traits are carried by the chromosomes that determine a person's gender |
| color-blindness | example of a sex-linked trait |
| genetics | the scientific study of heredity |
