Humans are bio-psycho-social-spiritual beings. Which biologically had been classified as either male or female based on body anatomy, we know that in the biological level is the chromosomes that define this features, where XX is for female and XY for male, so even before birth babies can have their gender defined.
The biological classification of gender implies certain social roles and functions, that may vary from society to society. In some societies these roles play down women in many different ways, historically women were treated as inferior in some societies and had to deal with things as receiving less wages than man in the same job position, or were not allowed to vote or to work in some specific jobs or places.
Now days great discussion occurs between scientist, philosophers and social scientist about what does it mean to be male or female? because even with this biological characteristics other elements can disrupt this dichotomous definition of male and female requiring then that we look for the integrity of humanity as beings that are bio-psycho-social-spiritual, not simply male or female which are compromised with some specific social role or function in a society.