What is the smallest unit that can carry out life processes in organisms?

• A. Atom
• B. Molecule
• C. Cell
• D. Spine

Answer: (C)

Life processes are carried out inside cells. An atom or a molecule can participate in metabolic reactions, but they don’t independently sustain the organized, self-maintaining activities that define living systems. A cell provides the necessary organization: a membrane to separate the inside from the outside, cytoplasm with enzymes, genetic material to store and transmit information, and organelles to carry out specific tasks like energy production and protein synthesis. In single-celled organisms, the entire life process happens within one cell; in multicellular organisms, many cells collaborate, but each cell still performs the essential life functions. A spine, on the other hand, is just a structural component and does not itself carry out life processes.