1.) specific characteristic of an organism that can be determined by genes or the environment
2.) hair color, body shape <<< easy to see
blood type, leaf shape. >>>> not easy to see
3.) Environmental factors often influence traits independently of genes. But not always. Sometimes the environment changes a gene—either its DNA sequence or its activity level. Either of these effects can change the proteins that are made from a gene, which in turn affects traits.
example: food, sunlight, temperature