Characteristics of Living Organisms - The Living World, Biology, Class 11
Living organisms exhibit several key characteristics that distinguish them from non-living things. These characteristics help us understand the complexity and diversity of life on Earth.

1. Cellular Organization:
Living organisms are composed of one or more cells. Cells are the basic structural and functional units of life. They carry out various processes necessary for the organism to survive and reproduce.

2. Growth and Development:
Living organisms have the ability to grow and develop over time. Growth involves an increase in size or number of cells, while development refers to changes in the organism's structure and function as it matures.

3. Metabolism:
Living organisms exhibit metabolism, which includes all the chemical reactions that occur within the cell to maintain life. These reactions involve the breakdown of nutrients to release energy and the synthesis of complex molecules for growth and repair.

4. Response to Stimuli:
Living organisms can respond to external stimuli from their environment. This ability allows them to adapt to changing conditions and maintain homeostasis, or internal balance.

5. Reproduction:
Living organisms reproduce to ensure the continuation of their species. Reproduction can occur through sexual or asexual means, depending on the organism.

6. Evolution:
Living organisms exhibit the capacity for evolution, which is the change in the genetic makeup of a population over time. This process leads to the diversity of life forms we see today.
Understanding these characteristics of living organisms is essential for studying biology and appreciating the complexity of life on Earth.