Acceleration is the rate of change of velocity with respect to time. In simpler terms, it refers to how quickly an object's velocity is changing. An object can accelerate if it is speeding up, slowing down, or changing direction.
From Molecules to Organisms: Structures and Processes
Obtain, evaluate, and communicate information to describe the function and diversity of organelles and structures in various types of cells (e.g., muscle cells having a large amount of mitochondria, plasmids in bacteria, chloroplasts in plant cells).