Cat senses roof of their mouths called the vomeronasal (or Jacobson's) organ. When a cat wrinkles its muzzle, lowers its chin, and lets its tongue hang a bit, it is opening the passage to the vomeronasal. This is called "gaping", "sneering", "snake mouth", or "flehming". Gaping is the equivalent of the Flehmen response in other animals, such as dogs, horses and big cats. A cat has about twenty-four movable vibrissae ("whiskers"), in four sets on each upper lip on either side of its nose (some cats may have more). There are also a few on each cheek, tufts over the eyes, bristles
A-side and B-side which would quickly replace the 78 for single record releases. The term "single" came into popular use with the advent of vinyl records in the early 1950s. At first, most record labels would randomly assign which song would be an A-side and which would be a B-side. (All records have specific identifiers for each side in addition to the catalog number for the record itself; the "A" side would typically be assigned a sequentially lower number.) Under this random system, many artists had so-called "double-sided hits", where both songs on a record made one of the national sales charts (in