The characteristics or features of living organisms are collectively known as the criteria of life. These characteristics are used to distinguish living things from non-living things and include the following:
- Organization: Living
organisms are made up of cells, tissues, organs, and systems that are
organized and function together as a unit.
- Metabolism: Living organisms
are able to perform chemical reactions, known as metabolism, to acquire
energy from food and use it to maintain their internal processes and
perform other functions.
- Response to stimuli: Living
organisms are able to respond to stimuli, such as changes in their
environment or the presence of danger, and adjust their behavior
accordingly.
- Growth and development:
Living organisms are able to grow and develop, either through the
accumulation of mass or by changes in their internal structure.
- Reproduction: Living
organisms are able to produce offspring, either sexually or asexually,
that can grow and develop into new individuals.
- Evolution: Living organisms
are able to evolve over time through the process of natural selection,
where the fittest individuals are more likely to survive and pass on their
genes to their offspring.
These criteria are not absolute and some exceptions
exist, such as viruses, which lack some of these features but are still
considered to be alive. Nevertheless, these characteristics are generally
accepted as the defining features of living organisms.