What term describes must-behavior, the basic and important patterns of ideas and acts within a culture?

The term that accurately describes must-behavior, which includes the essential patterns of ideas and actions within a culture, is "mores." Mores represent the fundamental social norms that are considered vital for the functioning of society. They are deeply ingrained and often carry moral significance, reflecting a society's values and ethical standards. Violating mores typically leads to severe consequences and censure because they relate to core values of a culture.

Values, while closely related, refer more broadly to beliefs about what is important and desirable in life. Norms denote general guidelines of behavior that are expected in particular situations but can vary in their importance and can be less rigid than mores. Customs are practices that are habitual or traditional within a culture but may not have the same moral weight as mores. Thus, "mores" best encapsulates the concept of must-behavior inherent to a culture.