Since ancient times, humanity has tried to understand the insides within us. Ancient Egyptians they handled human organs as they removed them for embalming. Medical manuscripts found in an ancient Chinese tomb could be i the earliest known anatomical writing on the human body. Thousands of years later, do we know how many organs there are in the human body?
Organs are collections of tissues that work together for a common goal, explained Lisa M.J. Lee, an associate professor in the Department of Cellular and Developmental Biology at the University of Colorado School of Medicine. “Each organ provides a function for human performance or survival,” he told Live Science.
But not all organs are necessary for survival. Only five organs ̵
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As for organ counts in the human body, it depends on who you ask and how you count, Lee said. Although no one knows where the number came from, the overall count is 78 organs, he said. This list includes the vital organs: the tongue, stomach, thyroid, urethra, pancreas, plus many other singles or pairs of organs. Bones and teeth they are counted only once.
Among anatomists, views differ on what counts as an organ. A histologist like Lee, who studies tissue at the microscopic level, may have a longer list of organs than a macroscopic anatomist, who studies what is visible to the naked eye. For example, scientists made headlines in 2017 for labeling the mesentery, which attaches the intestine to the abdominal wall, like an organ. While scientists have provided new evidence to call it an organ, it hasn’t been controversial, as many histologists and anatomists have agreed, Lee explained. But there is no group in charge of keeping an official organ count or deciding what qualifies as an organ.
Thinking under the microscope, when multiple types of tissues come together and function together, the unit is an organ, he said. Lee might call a nail, or structures that support the nail, an organ and count each tooth as an individual organ. “I would consider every bone an organ, and all 206 bones collectively are considered an organ system.” Since bones are already listed once in the 78 list, to get a count of the total number of organs using this definition, simply add 205, for a total of 284 organs.
Counting each tooth separately brings the list to 315 organs. Many other organs are listed only once, although there are many throughout the body. For example, ligaments and tendons could greatly increase the total number of organs when counted individually. This game is endless. The 78 list only counts nerves once, but there are trillions of them.
Exhausted? Lee often tells his medical and graduate students that he agrees with this kind of ambiguity. However you count them, you should take care of the organs you have, he added. “More and more, I am discovering how important it is that you put the right stuff in your body to nourish your cells, tissues and organs,” said Lee. After all, the body only has so many performers at its organ concert.
Originally published in Live Science.