Without bringing religion into this, is there such thing as actual right and wrong?

From a scientific, biological, and cultural standpoint, do Wrong and Right exist? Are we born with a moral code, or is it entirely a result of culture? What is the line between right and wrong, who decides, and how can most be repulsed by things that are normally considered "wrong" - like murder, , , and theft - if there are still people who do these acts? Do they not also have this inborn sense of right and wrong? Does this mean it does not come naturally?