Final answer:
Intergenerational mobility results in different social classes across generations of a family, while intragenerational mobility involves changes in social class within an individual's lifetime, reflecting personal circumstances or structural societal shifts.
Step-by-step explanation:
Intergenerational mobility refers to a difference in social class between different generations of a family, whereas intragenerational mobility refers to changes in a person's social class over the course of their lifetime. Patterns of intergenerational mobility can reflect long-term societal changes such as when an upper-class executive has parents from the middle class, and those parents were raised in the lower class. Individuals can experience upward mobility by moving from a lower to a higher socioeconomic class, or downward mobility which involves a lowering of one's social class, possibly due to setbacks such as unemployment or illness. Social mobility is key to understanding how individuals navigate the social stratification system and how structural changes in society can affect entire groups within the class ladder.