Biological organisms are living entities that exhibit characteristics such as growth, reproduction, and response to stimuli. They can be classified into various categories, including plants, animals, fungi, and microorganisms. Each type plays a unique role in ecosystems and contributes to the diversity of life on Earth. These organisms are made up of cells, which are the basic units of life. Cells carry out essential functions, such as metabolism and energy production. Biological organisms interact with their environment and other organisms, forming complex relationships that sustain life and promote ecological balance.