Each level works together to make the organism by combining what they do and doing it together. Also they have similar functions. If one was taken away, then the organism would die
The Levels of Organization
Tissues are groups of similar cells the perform a common function. Some examples are epithelial, muscle, nervous, and connective.
Organ systems are groups of organs that work together to perform a certain task. Examples are circulatory, reproductive, digestive, nervous, and respiratory.
Cells are the basic units of all living things. Some examples are the Euglena, Paramecium, Volvox, and Amoeba.
An organism is an individual animal, plant, or single-celled life form. Some examples are humans, plants, and animals.
An organ is a structure made of two or more different tissue types that work together to do a certain job. Some examples are a heart, lungs, and your esophagus.