Old-school Hollywood editors cut unwanted frames of film and patched in desired frames to make a movie. The human body does something similar—trillions of times per second—through a biochemical editing process called RNA splicing. Rather than cutting film, it edits the messenger RNA that is the blueprint for producing the many proteins found in cells.
source https://www.lifetechnology.com/blogs/life-technology-news-blog/like-film-editors-and-archaeologists-biochemists-piece-together-genome-history