The Company(Season 7, Episode 20) ION. Morgan's missing cousin, Cindi, reappears, and Morgan must come clean about a lie he told concerning her. In addition, the BAU reopens the investigation into Cindi's disappearance.
Selenium in biology. Although it is toxic in large doses, selenium is an essential micronutrient for animals. In plants, it sometimes occurs in amounts toxic as forage, e.g. locoweed. Selenium is a component of the amino acids selenocysteine and selenomethionine.
Selenium is one of the essential nutrients for humans, meaning that our bodies cannot make it, and so we have to get it from our diet. Without it the heart, joints, eyes, immune system or reproductive system can suffer.