Organism : a living thing that has an organized structure, can react to stimuli, reproduce, grow, adapt, and maintain homeostasis. Learn more and try the Organism Biology Quiz! An organism generally refers to a single or individual living species, which exhibits all the properties of life. These can be a plant, animal, bird, insect and even a microbe. There are billions to trillions of different types of organisms living on our planet Earth. Organisms can be defined as a living thing, a unique, complex organization exhibiting the following significant characteristics: Has cellular structure: Each living organism is a complex entity made up of protoplasm called living matter; contains biomolecules such as protein, nucleic acid, lipids, carbohydrates, etc. Can react to stimuli: Organisms can sense the external factors and respond accordingly. Can grow: Organisms can increase the mass of an individual. Reproduce: Organisms can form ... Learn what an organism is, how it is classified into domains and kingdoms, and see examples of different types of organisms. Find out how organisms interact with each other and their environment in various ways.
