Rachel White (Ginnifer Goodwin) is a single attorney working in a New York law firm. After too many drinks on her 30th birthday, Rachel grabs a cab with her friend, Dex (Colin Egglesfield) and playfully reveals she has had a crush on him since law school.
The elements in Group II also make positive ions, but instead of losing a single electron, their atoms lose 2 electrons when they turn into ions: you will find these metals in the second column of your periodic table so they are Group II.
An ion is a charged particle, such as Na+, the sodium ion. It has a positive charge, because it is missing one electron. Other ions, of course, are negatively charged. Cells have membranes that are made of lipid molecules (fats), and they prevent most things from entering or leaving the cell. But all over a cell membrane are proteins that stick out on both sides of the cell membrane. Some of these are ion channels.