Ciliate conjugation is a sexual phenomenon that results in genetic recombination and nuclear reorganization within the cell. In most ciliate groups, however, the cells separate after conjugation, and both form new macronuclei from their micronuclei.
Before the bun, hamburgers are said to have been served between two pieces of bread. In fact, a ground beef patty was known as Hamburger steak (first mentioned in an American cookbook in 1891); when this was put between bread or in a bun it was called a Hamburger sandwich.
The term Hamburger comes from Hamburg, Germany where the ground beef patty sandwich first became popular. A Beef Burger is exactly the same as a Hamburger, though it is often used to avoid confusion in areas with a high muslim or jewish population where pork is unpopular or disallowed.