Step-by-step explanation:
heredity determines some of the physical aspects such as the color of the eyes,the hair ,the skin etc
it also influences height and diseases and also personality
heredity also influences behavior since eg a son may have the same qualities such as braveness from his father
genes tend to change according to the environmental conditions eg when the early man started to light fire the fur from his skin shed hence that is a genetic mutation which is a change in genes caused by environmental chnges