* Metabolism: The organism takes in nutrients, converts them into energy, and eliminates waste products.
* Growth: The organism increases in size and complexity.
* Reproduction: The organism creates copies of itself.
* Response to stimuli: The organism reacts to changes in its environment.
* Homeostasis: The organism maintains a stable internal environment.
These functions are carried out by specialized structures within the cell, called organelles. For example, the nucleus contains the organism's genetic material, the mitochondria are responsible for energy production, and the cell membrane regulates what enters and leaves the cell.
Therefore, a single-celled organism is able to survive because it can perform all the necessary life functions within its single cell thanks to the specialized organelles it contains.
