| A | B |
|---|
| Trait | A characteristic that can be inherited from parents; it identifies an organism as an individual |
| Offspring | A new organism that results from reproduction |
| Heredity | The passing down of traits from parents to offspring |
| Crossbreeding | The matching of parents with different traits to produce offspring with new traits |
| Hybrid | The offspring of parents that have been crossbred |
| Dominant | Describes a trait that will show its effect no matter the effect of its partner trait |
| Recessive | Describes a trait that will be masked by a dominant partner trait |
| Chromosome | A threadlike structure in a cell nucleus that holds thousands of bits of information about an organism's traits |
| Gene | A bit of information in a chromosome |
| Mutation | A change in the genetic code of an organism |
| Evolution | The process of change in a species over time, usually over thousands or millions of years |
| Extinct | No longer existing on Earth |
| Fossil | The remains of an organism that lived long ago |
| Paleontology | The scientific study of fossils |
| Theory | An explanation about something that is supported by data |
| Naturalist | A scientist who studies living things in nature |
| Natural selecction | The way organisms that are best suited to their environment survive and pass on their helpful traits to offspring |
