biological sex (genetics and anatomy),
sexual preference (different than yourself, same as yourself),
gender expression/identity (how you present your self to the world, how you want the world to perceive you, how you interact with others).
THE PARTS ARE EACH INDEPENDENT OF THE OTHERS, WHERE YOU ARE ON ONE PART DOESN T HAVE ANYTHING TO DO WITH WHERE YOU ARE ON EITHER OF THE OTHER TWO PARTS. A GOOD DEFINITION OF THE THREE MAY BE THAT SEX IS BETWEEN YOUR LEGS , GENDER IS IN YOUR HEAD, AND SEXUAL ORIENTATION IS WHO YOU LOVE.