Hydrochloric Acid (HCl) is produced by the stomach and has the job of breaking down proteins. If you make plenty of HCl, then the body can adequately digest protein. If not, protein digestion is compromised.
A testable hypothesis must be just that--testable. You must be able to provide evidence that your hypothesis can be proven true in order for it to be considered accurate enough for future use among scientists. This can be done through repeated experimentation.
Stratification in the field of ecology refers to the vertical layering of a habitat; the arrangement of vegetation in layers. ... strata) of vegetation largely according to the different heights to which their plants grow. The individual layers are inhabited by different animal and plant communities (stratozones).