The basic unit of structure and function in living things is which of the following?

• A. Tissue
• B. Cell
• C. Organ
• D. Organism

Answer: (B)

The basic unit of structure and function in living things is the cell. Cells are the smallest units that can carry out all the life-sustaining processes, from energy production to growth and reproduction. They form the structural foundation of organisms and house the machinery (like organelles) that runs metabolism, protein synthesis, and waste removal. Some organisms consist of a single cell, while others are built from many cells organized into tissues, organs, and organ systems. Tissues are groups of similar cells working together; organs are made of multiple tissue types that perform a specific function; and an organism is an individual living being made up of one or more organ systems. Thus, the cell is the fundamental unit that both constitutes structure and drives function.