This may occur when one group feels threatened, but are themselves powerless to act against the actual source of the threat. All of the above are rather psychological. There is also the social context. Our attitudes and behaviors are learned within a social context. There are two forms of discrimination.
Institutional discrimination refers to unequal treatment that is entrenched in social institutions .
One example would be segregated housing. Another idea here would be the concept of blocked opportunities. Women lack power relative to men. They do not hold high position and have fewer resources. Women are also developing a consciousness of themselves as a separate category of people with common interests.