Selecting a part or parts of the molecule can be done by clicking (or shift clicking) on the desired part or by using the selection marquee to enclose the desired portion. When just clicking on a part of the molecule, the topmost element will be selected, even if there is something directly behind it. A click and drag movement of the mouse, using the selection marquee, will select all parts of the molecule that intersect the rectangle formed by the marquee, including any parts that may be obscured from view. Whatever was selected will be outlined by "moving ants."
