Sex refers to the biological distinction between females and males. Primary sex characteristics = the genitals (organs used for reproduction) Secondary sex characteristics = bodily development, aside from the genitals, that distinguished biologically mature females and males apart. Females wider hips for giving birth, milk producing breasts, fatty tissue acting as a reserve of nutrients during pregnancy and breastfeeding. Males more muscle in upper body, more extensive body hair, deeper voices: these are general characteristics, but it may be the case that some females have more body hair or some men have higher voices. Intersexual people people whose bodies, including genitals, have both female and male characteristics (aka. Hermaphrodites: has both female ovaries and male testes, in north america, people respond to hermaphrodites with confusion or fear, whereas other cultures are more accepting or indifferent to them. Gender identity traits that females and males, guided by their culture, incorporate into their personalities.