Search

DEFINITION: Exenteration is a major surgical procedure in which the entire contents of a body cavity, such as the pelvis or the orbit (eye socket), are totally removed.

Vestigiality refers to the evolutionary retention of genetic structures or functions that have lost all or some of their ancestral function over time. Bodily organs, structures, and functions that no longer serve any purpose are typically said to be vestigial. Scientists believe that such features become vestigial over a long period, as evolution gradually eliminates organisms' dependence on them for survival. Some examples of vestigial human body parts and functions include the appendix, the plica semilunaris, and wisdom teeth. Vestigiality occurs in nonhuman animal species as well. The sightless eyes of cave-dwelling fishes and the apparently useless wings of flightless birds are among the most common examples of nonhuman vestigiality. Many experts point to vestigial organs and functions as proof of evolution. Although this connection is not universally accepted, the concept of vestigiality nonetheless offers some important clues about how evolution works and what causes living things to change over time.

Organ trading involves the commercial exchange of organs (and their accompanying tissue structures) to provide sufficient numbers of healthy organs for transplantation procedures. Although essentially any organ in the body can be eligible for transplantation, the dominant organs are the kidneys, the heart, and the liver. In the age of cutting-edge medical technologies that, since the 1990s, have entirely revolutionized the surgical protocols for replacing damaged organs through transplantation to the point where such procedures, once considered highly risky and rare, have become among the most commonly performed surgeries in the world, the organ trade has emerged as one of the most hotly debated issues in bioethics. The problem is a question of free market dynamics and elemental economics: the demand is greater than the supply, as those who need healthy organs far outnumber those willing to donate organs.

There are nine main systems in the human body—the nervous, cardiovascular, respiratory, gastrointestinal, renal, endocrine, reproductive, thermoregulatory, and musculoskeletal systems. These systems are essential to sustain life, and they work together to perform their functions efficiently. All the other systems need the to operate or coordinate their functions. The first six of these systems are discussed in this article.