A complete living thing is called what?

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

Answer: (A)

A complete living thing is called an organism. An organism is any individual life form that can carry out the basic life processes—growth, metabolism, reproduction, response to stimuli, and maintaining homeostasis—on its own. A cell is the smallest unit of life that can be alive, and an organism may be single-celled or multicellular. A tissue is a group of similar cells performing a specific function, and a system is a set of organs that work together to fulfill a larger function. Because a single organism, whether a bacterium or a human, is able to carry out all necessary life processes independently, it is considered an organism. In multicellular organisms, many cells combine to form tissues, which combine to form organs and organ systems, all of which support the life of the organism as a whole.