Abstract: A rotating spinner travels down a number of track segments by the force of gravity, the spinner jumping across gaps separating the track segments and yet remaining in an upright position to enable reliable transfer of the spinner across the gaps. This is accomplished by designing the back spinner disk to have a weight that counterbalances the weight of the front spinner disk for thwarting tilting of said spinner member. The flat face of the spinner disk is large to display a large graphic design that moves as the spinner is transported down the track segments. A target member receives the spinner upon termination of its travel along the head-to-tail positioned track segments, and the skill level is changed by changing the gap sizes between track segments and the positions of the magnetized track segments supported upon a refrigerator door by force of gravity.

Abstract: A procedure for isolating high molecular weight nucleic acids utilizing a mixture of lytic enzymes and a chaotropic agent to complete protein denaturation and dissociation from nucleic acids is provided. The nucleic acids so obtained are useful for restriction enzyme analysis and DNA probe hybridization.