Enzymes are produced by groups of cells and tissues called blank

Organ

Explanation:

Aggregation of cells results in tissue formation. Aggregation of Tissues results in the formation of Organs.

Enzymes are produced in organs of the body such as the Pancreas, Stomach, Mouth which are all associated with the the food digestive aspect of the body.

The enzymes produced are used in speeding up biochemical processes and in the enhanced and efficient breakdown of substances in the body.

the missing space is phylum