1. Phenotypes that decide the decide the development plan of the body do not vary in a population of organisms. Example, the segmentation of the body (number of hands, legs, ears, eyes, etc.).
2. Phenotypes that vary in a population are the eye color, hair color, hair growth, body size, body build, cold tolerance, skin color, etc.
3. Most of the phenotypes have a genetic basis, example, the colorblindness trait that is X linked inherited. But some phenotypes vary epigenetically, e.g., differences in body features of twins.
4. Yes, environment influences the phenotypes. Twins have a genetically identical DNA yet they have minute differences in their skin color, eye color, body build, etc. Such differences arise when the environment differently affects the gene regulation within the body of the twins.
Normally tree rings will disappear, damage, or go missing when the tree doesn't have enough nutrients, another factor that contributes to that is drought.
Answer:
I think its B because An insertion changes the number of DNA bases in a gene by adding a piece of DNA. As a result, the protein made by the gene may not function properly. But it could be C because Missense mutation is a change in one DNA base pair that results in the substitution of one amino acid for another in the protein made by a gene.