Best Times to Go to Florence, Italy. Avoid summers if you can, it's hot and packed with sweating tourists in July and August. That said, there's hardly a time you won't encounter tourists in Florence. If you must go in summer, make hotel reservations early.
Helical. Helical (adjective) is having a spiral form of many rounds. Helical can be a hairstyle curl, loop fold of a ribbon that serves as pony and a repeated dialogue of an actor that gives twist to the audience.
DNA helicase is an enzyme that unwinds the DNA double helix by breaking the hydrogen bonds between the complementary bases. It's easy to remember the name because it has part of the word helix in it. You can imagine it sort of as a wedge that forces apart the two strands, just like the slider on a zipper wedges apart the two long rows of teeth.