In biology, the active site is the region of an enzyme where substrate molecules bind and undergo a chemical reaction. The active site consists of residues that form temporary bonds with the substrate (binding site) and residues that catalyse a reaction of that substrate (catalytic site).
Seattle is rolling out 11 rainbow crosswalks in Capitol Hill this week, adding a colorful bang to the annual Pride celebration. The crosswalks cost the city $66,000, said Seattle Department of Transportation spokesman Rick Sheridan, and are permanent.
While no cost estimate for this crossing is available, it would appear from an examination of the costs of similar projects in the New York metropolitan area that a single-tube tunnel could be constructed for about $35,000,000, and a two-tube tunnel for about $60,000,000.