A. Good question. Under most circumstances, no. In its early stages, which is where most research is now, genetic research rarely leads to medically useful information for individuals that might lead to treatment or prevention. The State of California broke the code linking names to numbers in order to warn the parents, so they could use preventive measures. There is no national policy about notifying people, however.
Most research uses thousands of samples to produce a result.
Usually yours is not unique in contributing to the outcome. There have been rare cases, however, in which an individual's DNA has contained something uniquely useful. We don't know about the frog. Pathology samples have been used in just about every kind of research that is legal. Federal regulations currently prohibit research on the human embryo, so you don't need to worry about that.