A variety of practices and specialised representational systems are required to understand, communicate and construct molecular genetics knowledge. This study describes teachers' use of multimodal representations of molecular genetics concepts and how their strategies and choice of resources were interpreted, understood and used by students to…

Argues that inventions are of the utmost importance in knowledge development, and that conventions play an important role in inventions by providing support for their development. This position borrows from Piaget's perspective regarding figurative and operative aspects of thought. Contains 22 references. (DDR)