Motor proteins provide for molecular transport of materials in cells by interacting with CYTOSKELETAL STRUCTURES.
Cytoskeletal structures refers to those structures in the cells that provide basis for movement from one part of the cell to another.
Motor protein work together with cytoskeletal structures to carry different type of materials from one point of the cell to another point.
Your answer is Burning of fossil fuels
Involuntary action in body
Secondary succession happens more often because it occurs after some kind of distribution that still leaves the soil intact (mudslide,bulldozing,shoveling,or scraping off an area)