Question

In the organization of living things, tissues combine to form?

Answer 1

An organ. 
organs combine to form an organ system 

Answer 2

Answer: to form Organ

Explanation: Living things are very structured and organized, the follow a hierarchy or order and they carry out their unique indispensable functions. The mitochondria produces energy which powers the cell, then the cell come together to form tissues, tissues form organs, organs come together to form organ systems and the organ system combines to form an organism.