Question

used meat in three different sets of jars to show that living things can only come from living things.

used a map to show that cholera was caused by contaminated water and not poisonous vapors.

boiled meat broth in different flasks to prove that living things did not spontaneously generate.

Answer 1

- Francesco Redi — used meat in three kinds of jars (open, sealed, and covered with gauze) to show that maggots on meat came from fly eggs, not spontaneous generation (1668).
- John Snow — mapped cholera cases in London and traced the outbreak to a contaminated Broad Street water pump, showing water — not miasma — transmitted the disease (1854).
- Louis Pasteur — boiled nutrient broth in swan‑neck flasks; broth remained sterile until the flask neck was broken, disproving spontaneous generation (1861).