What concept did Louis Pasteur confirm regarding the origin of cells?

Louis Pasteur famously conducted experiments that supported the idea that cells arise from other living cells, which is foundational to the cell theory. His notable experiments involved sterilizing broth and demonstrating that, when isolated from microorganisms, it remained free of life. However, when exposed to air, the broth would become contaminated, showcasing that microorganisms came from other living cells rather than spontaneously generating from nonliving matter.

This confirmation of biogenesis, or the concept that life arises from pre-existing life, fundamentally contradicted the longstanding belief in spontaneous generation, which proposed that living organisms could emerge from nonliving substances. Pasteur’s work laid the groundwork for modern microbiology and the understanding of infectious diseases, reinforcing the importance of other living cells in the generation of new cells.