Question

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1. in 1859, french chemist louis pasteur placed sterile nutrient broth in two different

flasks. he allowed both flasks to come into contact with air. however, one flask was
designed to prevent any air particles from reaching the broth. he then observed that
growth only occurred in flask 1 and not in flask 2.
flasks used by pasteur.

flask 1 flask 2
in terms of today’s modern cell theory, what did pasteur prove?

Explanation:

Louis Pasteur's experiment tested the idea of spontaneous generation. Flask 1 allowed airborne particles (containing microorganisms) to reach the broth, leading to growth. Flask 2's curved trap stopped particles from entering the broth, so no growth occurred. This directly supports the modern cell theory principle that living cells only come from pre-existing living cells, not non-living matter.

Answer:

Pasteur proved that living cells (the growth observed in the broth) can only arise from pre-existing living cells (carried by airborne particles), disproving spontaneous generation and confirming a key tenet of modern cell theory: all cells come from pre-existing cells.