Brown adipose tissue is present in small mammals (e.g., mice) and in newborn humans. Most of it disappears in adult humans. The cells in both types of fat are called adipocytes although they differ in origin, structure, and function in the two types of tissue.
On the left hand, index finger. It's not the index finger you wear it on. Left hand, ring finger. The finger that you would wear a wedding ring on.
Generally, engagement and wedding rings are not divisible in a divorce, but other jewelry and gifts given during a marriage may be considered marital property that can be divided by a divorce court. However, laws vary among states.