noun, plural: organs
A group of tissues that perform a specific function or group of functions
An organ pertains to a group of tissues that perform a specific function or group of functions. Typically, an organ would have the main tissue component that characterizes the organ and other tissues, such as those associated with the organ’s structure and function. For instance, in animals, an organ would usually consist of the main tissue together with the parenchymal (functional) and the stromal (structural) tissues. In particular, the heart is comprised of the myocardium as the main tissue component and other tissues such as nerves, connective tissues, and blood vessels. In animals, organs include heart, lungs, brain, eye, stomach, spleen, bones, pancreas, kidneys, liver, intestines, skin, urinary bladder and sex organs. In plants, organs include roots, stems, leaves, flowers, seeds and fruits.
Organs that are functionally related comprise the so-called organ system. For example, the human cardiovascular system whose primary role is to pump and channel blood to and from the body and lungs is comprised of heart, blood, and blood vessels.
Word origin: Latin organum
- ogan system