Characteristics of Organisms
Every organism - whether it's a plant, animal, or microbe - performs several essential life processes. These characteristics are what make something "alive" rather than just an object.
All living things grow, starting small and becoming larger by adding cells or increasing cell size. They also exhibit movement, though this looks different across species - animals typically move their whole bodies while plants slowly move parts of themselves toward light or water.
Sensitivity is another key trait - organisms detect changes in their environment and respond accordingly. They also perform excretion, removing toxic waste products that result from their metabolic processes.
Fun Fact: While we often think of movement as walking or swimming, even single-celled organisms can move! Bacteria use tiny hair-like structures called flagella to propel themselves through liquids.
Living things also share the ability for reproduction, creating new organisms of the same species. They obtain nutrition by taking substances from their environment to provide energy and building materials. Finally, all organisms perform respiration, breaking down glucose and other substances inside their cells to release usable energy.