Pasteur used tipped and untipped sterilized S-shaped flaks of broth in an attempt to

Show that life can only come from life (rather than spontaneous generation)

Explanation:

Pasteur boiled a broth in a flask with an S-shaped neck. Thebend in the neck prevented particles from the air reaching the broth, but still allowed air to get in.  No bacteria grew in the flask.  

When the flask neck was broken so that particles could get inside, the broth became cloudy, showing that microorganisms were only able to grow from other living things from the outside, and not spontaneously from nothing

answer; ///(statins)/aka as hmg coa