You are interested in the role that gene X plays in embryoge…

You are interested in the role that gene X plays in embryogenesis.  Specifically, you want to visualize via brightfield microscopy any morphological changes that may occur over the course of development in the absence of gene X.  Which model organism would be the best choice:

The generation of the knockout mouse model provided an impor…

The generation of the knockout mouse model provided an important tool for scientists to study genetics in mammals.  During the creation of a knockout line, a chimera is produced after implantation of the transfected embryo (embryo containing the desired genetic deletion) into the surrogate mother.  Which of the following best explains why?