It is a substance that takes part in and undergoes change during a reaction
Reticulum is the only one I know of that contain lysosmes.
Lots of hand waving as is in the current field of much of molecular biology. Other than that experiments and observations. Basically the utilization of the scientific method and then trying to find the mechanism by which something occurs through even more research/experimentation.
HOPE THIS HELPS
It is pH. If you have a pH of 0-6 it is a acidic. If you have a pH of 7 it is neutral. If you have a pH of 8 or above it is a base.
