Which term refers to the basic unit of life in all organisms?

Which term refers to the basic unit of life in all organisms?

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

Answer: (A)

The basic unit of life is the cell. This idea comes from cell theory, which states that all living things are made of cells and that a cell is the smallest unit capable of carrying out life processes like metabolism, growth, and responding to the environment. Some organisms are only a single cell, which must perform all life functions on its own. In multicellular organisms, many cells work together to form tissues, organs, and organ systems, but each individual cell still carries out essential life activities. Molecules are the chemical building blocks of life, but they don’t perform life processes by themselves, so they aren’t the basic unit of life. In the skin, for example, skin cells continually renew the epidermis, illustrating how life operates at the cellular level.

The basic unit of life is the cell. This idea comes from cell theory, which states that all living things are made of cells and that a cell is the smallest unit capable of carrying out life processes like metabolism, growth, and responding to the environment. Some organisms are only a single cell, which must perform all life functions on its own. In multicellular organisms, many cells work together to form tissues, organs, and organ systems, but each individual cell still carries out essential life activities. Molecules are the chemical building blocks of life, but they don’t perform life processes by themselves, so they aren’t the basic unit of life. In the skin, for example, skin cells continually renew the epidermis, illustrating how life operates at the cellular level.