A gender role is a set of societal norms dictating the types of behaviors which are generally considered acceptable, appropriate, or desirable for people based on their actual or perceived sex or sexuality. Gender roles are usually centered on conceptions of femininity and masculinity, although there are exceptions and variations. The specifics regarding these gendered expectations may vary substantially among cultures, while other characteristics may be common throughout a range of cultures. There is ongoing debate as to what extent gender roles and their variations are biologically determined, and to what extent they are socially constructed.