Final answer:
The correct order is cell, tissue, organ, organ system, organism, starting with cells as the basic unit of life and culminating in the complete organism.
Step-by-step explanation:
The correct order of levels of organization from smallest to largest is: cell → tissue → organ → organ system → organism. This organization is critical for understanding the structure and function of living organisms. Cells are the basic unit of life, organized into tissues. These tissues form organs, and those organs are grouped into organ systems, which work together to support the life functions of an organism, the highest level of organization.