Definitions
Biology
The study of life.
Cells
The basic unit of structure and function in living things.
Reproduction
The biological process by which new individual organisms are produced.
DNA
The carrier of genetic information in living organisms, determining the inherited traits.
Homeostasis
The ability of an organism or environment to maintain stability in spite of changes.
Evolution
The process by which different kinds of living organisms are thought to have developed and diversified from earlier forms.
Characteristics of Life
Living Things are Made of Cells
All living things are composed of one or more cells. Cells are considered the smallest units of life, and they can be unicellular, as seen in bacteria, or multicellular, like in plants and animals. Every cell has a specific role to play, and its organization determines the overall function of a living being.
Living Things Can Reproduce
Reproduction is essential for the continuation of a species. It can occur sexually, involving the combination of genetic materials from two parents, or asexually, where an organism can reproduce on its own. This process ensures the transfer of genetic material to the next generation.
Living Things are Based on a Universal Code (DNA)
Deoxyribonucleic acid (DNA) serves as the universal genetic code for all living organisms. It carries instructions for growth, development, functioning, and reproduction, making it a fundamental component of life.
Living Things Grow and Develop
Growth and development are crucial aspects of life. Growth refers to an increase in size and mass, while development is the progression through various life stages. These processes result from cell division and differentiation.
Living Things Obtain and Use Material and Energy
To sustain life, organisms must intake materials and energy, transforming them into forms necessary for survival and reproduction. This process involves metabolism, a series of chemical reactions that allow for growth, reproduction, and maintenance.
Living Things Respond to Their Environment
Living organisms can detect and respond to changes in their environment, which is crucial for survival. This responsiveness ensures that they can adapt to new conditions, avoid harm, and approach beneficial opportunities.
Living Things Maintain a Stable Internal Environment (Homeostasis)
Homeostasis refers to a living organism's ability to regulate internal conditions such as temperature, pH, and water balance. This constant regulation allows the organism to function effectively regardless of external changes.
Living Things Change Over Time (Evolution)
Evolution is the change in heritable traits of biological populations over successive generations. It allows living organisms to adapt to their environment, survive various changes, and potentially develop new species.
To remember :
In summary, the eight characteristics of life collectively define what it means to be 'alive.' They highlight the complexity, adaptability, and incredible resilience of living organisms. From maintaining cell structures and reproducing to evolving as populations, these characteristics ensure the survival and continuous growth of life on Earth.
