You have two kidneys, each about the size of a fist, located on either side of the spine at the bottom of the rib cage. Each kidney contains about one million functioning units called nephrons. A nephron consists of a filtering unit of tiny blood vessels, called a glomerulus, which is attached to a tubule. When blood enters the glomerulus, it is filtered and the remaining fluid then passes through the tubule.
In the first case, each time the computer starts up, the question mark appears and flashes for a few seconds, then disappears. The cause of this symptom is that there is no hard drive selected in the Startup control panel. Remember that selected on the Macintosh means that an icon is darker than the other.
A green circle with a check mark is a wonderful thing and what you'll see most often. When it appears on an individual file or folder, it means the file or folder has finished syncing the latest changes. Sync in progress. The blue circle with rotating arrows is another great sign that your Dropbox is running smoothly.