This is a kidney cell dividing, a process called mitosis in which a cell nucleus splits in two, followed by division of the parent cell into two daughter cells. The word "mitosis" means "threads," and it refers to the threadlike appearance of chromosomes as the cell prepares to divide.

NOTE: The imagery of this NFT is not unique (it is from a widely circulated video from Nikon Instruments), however at the point of minting there's been no NFTs created from the same source.