The mutation in the FBN1 gene that causes Marfan syndrome influences the phenotypic outcomes of several traits in the human body (elongated head, limbs, and digits; lung and eye problems; and heart valve and vessel defects). In your current research you identify a second gene, called FCD3, whose expression is affected by the FBN1 mutation. This scenario of genes interacting with each other to determine phenotype is an example of .

epistasis

Explanation:

Epistasis refers to the genetic mechanism by which the expression of one gene is affected by the expression of other gene/s. In epistasis, two or more genes interact with each other in order to determine a phenotypic trait, thereby a particular gene contributes or masks the expression of other gene/s. In humans, the gene for albinism (absence of melanin pigment) is an example of an epistatic gene that prevents pigment formation and color formation. On the other hand, a pleiotropic gene is a single gene that affects more than one phenotypic trait (e.g., a mutation in a single gene that codes for phenylalanine hydroxylase enzyme results in multiple phenotypes associated with phenylketonuria disorder).

oceans

indian ocean

pacific ocean

atlantic ocean

arctic ocean

southern ocean

if your own plato the answer is b. the fern transitioned from sporophyte generation to gametophyte generation.