Accepted Answer. The Dragon Scale can be found on wild Horsea, Seadra, Dratini, and Dragonair. The only hitch to your plan is that you can only find them after getting the National Dex and Dratini and Dragonair can only be found by using the Super Rod, behind the Waterfall, at Mt. Coronet.
Microtubules are conveyer belts inside the cells. They move vesicles, granules, organelles like mitochondria, and chromosomes via special attachment proteins. They also serve a cytoskeletal role. Structurally, they are linear polymers of tubulin which is a globular protein.
Living cells have the capacity to move certain molecules and ions through the cell membrane against the normal direction of diffusion. That is, these substances can be moved form an area of lower concentration to an area of higher concentration.