Why is dissection an important part of a biology curriculum? Which animals and/or plants should be included in biological studies?

The biology curriculum is designed to continue student investigations and deepen student understanding of the biological sciences.  In-depth study of the following concepts is included: the cell, the molecular basis of heredity, biological evolution, the interdependence of organisms, matter, energy and organization in living systems, and the adaptive responses of organisms. In biology the plants are animals that we need to learn about is and endangered species and the plants that show the students the different processes of biology.
http://www.ncpublicschools.org/curriculum/science/scos/2004/23biology