The smallest unit of life is the cell. It is the fundamental structural and functional unit that can exist independently and carry out all life processes such as growth, reproduction, and metabolism. Cells make up all living organisms, from single-celled organisms like bacteria and yeast to complex multicellular organisms such as plants and animals. Cells contain essential components such as DNA and organelles, which perform specialized functions necessary for the cell to survive and function. Because cells can reproduce on their own, they represent the smallest unit capable of independent existence. Viruses are not considered living because they are not made of cells and require a host cell to reproduce. In summary:
- A cell is the smallest life unit capable of independent existence.
- All living organisms are made of one or more cells.
- Cells contain DNA and organelles that perform vital life functions.
- Cells can be unicellular or part of multicellular organisms.
Thus, the cell is often called the "building block of life" and represents the smallest unit of life in biology.
