What is the basic unit of life?

The basic unit of life is the cell. Cells are the smallest structural and functional units of living organisms, serving as the building blocks for all forms of life. They perform essential functions such as metabolism, energy production, and reproduction, allowing organisms to grow, develop, and respond to their environments.

While atoms are the fundamental units of matter, they do not have the characteristics of life. Tissues are groups of similar cells working together to perform a specific function, and organs are collections of different tissues that carry out particular tasks in an organism. Therefore, the cell stands out as the foundational unit that embodies all the essential features required to categorize something as living, making it the answer to this question.