Why is it impossible for humans to digest food that contains cellulose?

it impossible for humans to digest the food that contains cellulose because they do have an enzyme which is required to break beta acetal linkage.

Explanation:

cellulose is a polysaccharide and it is synthesized by animals, plants and in plant cell wall major component is cellulose.

it impossible for humans to digest the food that contains cellulose because they do have an enzyme which is required to break beta acetal linkage.

Ruminants such as cows in the rumen symbiotic anaerobic bacteria are present, cellulases enzyme is produced by these bacteria, that help to digest the cellulose.

      The right answer to this question is: we don't have a specific enzyme called Cellulase.

Explanation:

        An enzyme is basically a system known as lock and key mechanism. It works like this: every single enzyme has its own form, and there's only one way of getting into it for the digestion to happen, the substrate needs to complete this system, as a key on a lock, and once this happens, the digestion can start. But humans don't have this enzyme, if they don't have it, the digestion won't happen in this case. Well known animals that have it are the ruminants, they can digest cellulose easily because they have the specific enzyme called cellulase.