What is a group of cells that can do certain things as group called

Tissue

Explanation:

The levels of organization go as follows:

Atom - the building blocks of all living and nonliving material

Molecule - two or more atoms that join together in chemical bond

Organelle - two or more molecules working together to perform a particular function in a cell

Cell - the smallest unit that exhibits all of the characteristics of life

Tissue - two or more cells that work together to perform a particular function

Organ - two or more tissues that work together to perform a particular function

Organ System - two or more organs that work together to perform a particular function

Multi-Celled Organism - two or more organ systems that work together