Gray's Anatomy is an English language textbook of human anatomy written by Henry Gray and illustrated by Henry Vandyke Carter. Earlier editions were called Anatomy: Descriptive and Surgical, Anatomy of the Human Body and Gray's Anatomy: Descriptive and Applied, but the book's name is shortened to, editions are titled, Gray's Anatomy; the book is regarded as an influential work on the subject, has continued to be revised and republished from its initial publication in 1858 to the present day. The latest edition of the book, the 41st, was published in September 2015; the English anatomist Henry Gray was born in 1827. He studied the development of the endocrine glands and spleen and in 1853 was appointed Lecturer on Anatomy at St George's Hospital Medical School in London. In 1855, he approached his colleague Henry Vandyke Carter with his idea to produce an inexpensive and accessible anatomy textbook for medical students. Dissecting unclaimed bodies from workhouse and hospital mortuaries through the Anatomy Act of 1832, the two worked for 18 months on what would form the basis of the book.
Their work was first published in 1858 by John William Parker in London. It was dedicated by Gray to 1st Baronet. An imprint of this English first edition was published in the United States in 1859, with slight alterations. Gray prepared a second, revised edition, published in the United Kingdom in 1860 by J. W. Parker. However, Gray died the following year, at the age of 34, having contracted smallpox while treating his nephew, his death had come just three years after the initial publication of his Anatomy Descriptive and Surgical. So, the work on his much-praised book was continued by others. Longman's publication began in 1863, after their acquisition of the J. W. Parker publishing business; this coincided with the publication date of the third British edition of Gray's Anatomy. Successive British editions of Gray's Anatomy continued to be published under the Longman, more Churchill Livingstone/Elsevier imprints, reflecting further changes in ownership of the publishing companies over the years.
The full American rights were purchased by Blanchard and Lea, who published the first of twenty-five distinct American editions of Gray's Anatomy in 1862, whose company became Lea & Febiger in 1908. Lea & Febiger continued publishing the American editions until the company was sold in 1990; the first American publication was edited by Richard James Dunglison, whose father Robley Dunglison was physician to Thomas Jefferson. Dunglison edited the next four editions; these were: the Second American Edition. W. W. Keen edited the next two editions, namely: the New American from the Eleventh English Edition. In September 1896, reference to the English edition was dropped and it was published as the Fourteenth Edition, edited by Bern B. Gallaudet, F. J. Brockway, J. P. McMurrich, who edited the Fifteenth Edition. There is an edition dated 1896 which does still reference the English edition stating it is "A New Edition, Thoroughly Revised by American Authorities, from the thirteenth English Edition" and edited by T. Pickering Pick, F.
R. C. S. and published by Lea Brothers & Co. Philadelphia and New York; the Sixteenth Edition was edited by J. C. DaCosta, the Seventeenth by DaCosta and E. A. Spitzka. Spitzka edited the Eighteenth and Nineteenth editions, in October 1913, R. Howden edited the New American from the Eighteenth English Edition; the "American" editions continued with consecutive numbering from the Twentieth onwards, with W. H. Lewis editing the 20th, 21st, 22nd, 23rd, 24th. C. M. Gross edited the 25th, 26th, 27th, 28th, 29th. Carmine D. Clemente extensively revised the 30th edition. With the sale of Lea & Febiger in 1990, the 30th edition was the last American Edition. Sometimes separate editing efforts with mismatches between British and American edition numbering led to the existence, for many years, of two main "flavours" or "branches" of Gray's Anatomy: the U. S. and the British one. This can cause misunderstandings and confusion when quoting from or trying to purchase a certain edition. For example, a comparison of publishing histories shows that the American numbering kept apace with the British up until the 16th editions in 1905, with the American editions either acknowledging the English edition, or matching the numbering in the 14th, 15th and 16th editions.
The American numbering crept ahead, with the 17th American edition published in 1908, while the 17th British edition was published in 1909. This increased to a three-year gap for the 18th and 19th editions, leading to the 1913 publication of the New American from the Eighteenth English, which brought the numbering back into line. Both 20th editions were published in the same year. Thereafter, it was the British numbering that pushed ahead, with the 21st British edition in 1920, the 21st American edition in 1924; this discrepancy continued to increase, so that the 30th British edition was published in 1949, while the 30th and last American edition was published in 1984. The newest, 41st edition of Gray's Anatomy was published on 25 September 2015 by Elsevier in both print and online versions, and
The ear canal is a pathway running from the outer ear to the middle ear. The adult human ear canal extends from the pinna to the eardrum and is about 2.5 centimetres in length and 0.7 centimetres in diameter. The human ear canal is divided into two parts; the elastic cartilage part forms the outer third of the canal. The cartilage is the continuation of the cartilage framework of pinna; the cartilaginous portion of the ear canal contains small hairs and specialized sweat glands, called apocrine glands, which produce cerumen. The bony part forms the inner two thirds; the bony part is only a ring in the newborn. The layer of epithelium encompassing the bony portion of the ear canal is much thinner and therefore, more sensitive in comparison to the cartilaginous portion. Size and shape of the canal vary among individuals; the canal is 2.5 centimetres long and 0.7 centimetres in diameter. It runs from behind and above downward and forward. On the cross-section, it is of oval shape; these are important factors to consider.
Due to its relative exposure to the outside world, the ear canal is susceptible to diseases and other disorders. Some disorders include: Atresia of the ear canal Cerumen impaction Bone exposure, caused by the wearing away of skin in the canal Auditory canal osteoma Cholesteatoma Contact dermatitis of the ear canal Fungal infection Ear mites in animals Ear myiasis, an rare infestation of maggots Foreign body in ear Granuloma, a scar caused by tympanostomy tubes Otitis externa, bacteria-caused inflammation of the ear canal Stenosis, a gradual closing of the canal Earwax known as cerumen, is a yellowish, waxy substance secreted in the ear canals, it plays an important role in the human ear canal, assisting in cleaning and lubrication, provides some protection from bacteria and insects. Excess or impacted cerumen can press against the eardrum and/or occlude the external auditory canal and impair hearing, causing conductive hearing loss. If left untreated, cerumen impaction can increase the risk of developing an infection within the ear canal.
List of specialized glands within the human integumentary system Veterans Health Administration web site OSHA web site Continuing Medical Education Ear Photographs Otoscopy Tutorial w/ Images "Anatomy diagram: 34257.000-1". Roche Lexicon - illustrated navigator. Elsevier. Archived from the original on 2014-01-01
The oval window is a membrane-covered opening that leads from the middle ear to the vestibule of the inner ear. Vibrations that contact the tympanic membrane travel through the three ossicles and into the inner ear; the oval window is the intersection of the middle ear with the inner ear and is directly contacted by the stapes. It is a reniform opening leading from the tympanic cavity into the vestibule of the internal ear, it is occupied by the base of the stapes, the circumference of, fixed by the annular ligament to the margin of the foramen. Round window This article incorporates text in the public domain from page 1040 of the 20th edition of Gray's Anatomy Diagram at Washington University The Anatomy Wiz. Oval Window
Anatomical terminology is a form of scientific terminology used by anatomists and health professionals such as doctors. Anatomical terminology uses many unique terms and prefixes deriving from Ancient Greek and Latin; these terms can be confusing to those unfamiliar with them, but can be more precise, reducing ambiguity and errors. Since these anatomical terms are not used in everyday conversation, their meanings are less to change, less to be misinterpreted. To illustrate how inexact day-to-day language can be: a scar "above the wrist" could be located on the forearm two or three inches away from the hand or at the base of the hand. By using precise anatomical terminology such ambiguity is eliminated. An international standard for anatomical terminology, Terminologia Anatomica has been created. Anatomical terminology has quite regular morphology, the same prefixes and suffixes are used to add meanings to different roots; the root of a term refers to an organ or tissue. For example, the Latin names of structures such as musculus biceps brachii can be split up and refer to, musculus for muscle, biceps for "two-headed", brachii as in the brachial region of the arm.
The first word describes what is being spoken about, the second describes it, the third points to location. When describing the position of anatomical structures, structures may be described according to the anatomical landmark they are near; these landmarks may include structures, such as the umbilicus or sternum, or anatomical lines, such as the midclavicular line from the centre of the clavicle. The cephalon or cephalic region refers to the head; this area is further differentiated into the cranium, frons, auris, nasus and mentum. The neck area is called cervical region. Examples of structures named according to this include the frontalis muscle, submental lymph nodes, buccal membrane and orbicularis oculi muscle. Sometimes, unique terminology is used to reduce confusion in different parts of the body. For example, different terms are used when it comes to the skull in compliance with its embryonic origin and its tilted position compared to in other animals. Here, Rostral refers to proximity to the front of the nose, is used when describing the skull.
Different terminology is used in the arms, in part to reduce ambiguity as to what the "front", "back", "inner" and "outer" surfaces are. For this reason, the terms below are used: Radial referring to the radius bone, seen laterally in the standard anatomical position. Ulnar referring to the ulna bone, medially positioned when in the standard anatomical position. Other terms are used to describe the movement and actions of the hands and feet, other structures such as the eye. International morphological terminology is used by the colleges of medicine and dentistry and other areas of the health sciences, it facilitates communication and exchanges between scientists from different countries of the world and it is used daily in the fields of research and medical care. The international morphological terminology refers to morphological sciences as a biological sciences' branch. In this field, the form and structure are examined as well as the changes or developments in the organism, it is functional.
It covers the gross anatomy and the microscopic of living beings. It involves the anatomy of the adult, it includes comparative anatomy between different species. The vocabulary is extensive and complex, requires a systematic presentation. Within the international field, a group of experts reviews and discusses the morphological terms of the structures of the human body, forming today's Terminology Committee from the International Federation of Associations of Anatomists, it deals with the anatomical and embryologic terminology. In the Latin American field, there are meetings called Iberian Latin American Symposium Terminology, where a group of experts of the Pan American Association of Anatomy that speak Spanish and Portuguese and studies the international morphological terminology; the current international standard for human anatomical terminology is based on the Terminologia Anatomica. It was developed by the Federative Committee on Anatomical Terminology and the International Federation of Associations of Anatomists and was released in 1998.
It supersedes Nomina Anatomica. Terminologia Anatomica contains terminology for about 7500 human gross anatomical structures. For microanatomy, known as histology, a similar standard exists in Terminologia Histologica, for embryology, the study of development, a standard exists in Terminologia Embryologica; these standards specify accepted names that can be used to refer to histological and embryological structures in journal articles and other areas. As of September 2016, two sections of the Terminologia Anatomica, including central nervous system and peripheral nervous system, were merged to form the Terminologia Neuroanatomica; the Terminologia Anatomica has been perceived with a considerable criticism regarding its content including coverage and spelling mistakes and errors. Anatomical terminology is chosen to highlight the relative location of body structures. For instance, an anatomist might describe one band of tissue as "inferior to" another or a physician might describe a tumor as "superficial to" a deeper body structure.
Anatomical terms used to describe location
A beard is the collection of hair that grows on the chin, upper lip and neck of humans and some non-human animals. In humans only pubescent or adult males are able to grow beards. However, women with hirsutism, a hormonal condition of excessive hairiness, may develop a beard. Throughout the course of history, societal attitudes toward male beards have varied depending on factors such as prevailing cultural-religious traditions and the current era's fashion trends; some religions have considered a full beard to be essential for all males able to grow one, mandate it as part of their official dogma. Other cultures while not mandating it, view a beard as central to a man's virility, exemplifying such virtues as wisdom, sexual prowess and high social status. However, in cultures where facial hair is uncommon, beards may be associated with poor hygiene or a "savage," uncivilized, or dangerous demeanor; the beard develops during puberty. Beard growth is linked to stimulation of hair follicles in the area by dihydrotestosterone, which continues to affect beard growth after puberty.
Dihydrotestostorone promotes balding. Dihydrotestosterone is produced from the levels of which vary with season. Beard growth rate is genetic. Biologists characterize beards as a secondary sexual characteristic because they are unique to one sex, yet do not play a direct role in reproduction. Charles Darwin first suggested possible evolutionary explanation of beards in his work The Descent of Man, which hypothesized that the process of sexual selection may have led to beards. Modern biologists have reaffirmed the role of sexual selection in the evolution of beards, concluding that there is evidence that a majority of women find men with beards more attractive than men without beards. Evolutionary psychology explanations for the existence of beards include signalling sexual maturity and signalling dominance by increasing perceived size of jaws, clean-shaved faces are rated less dominant than bearded; some scholars assert that it is not yet established whether the sexual selection leading to beards is rooted in attractiveness or dominance.
A beard can be explained as an indicator of a male's overall condition. The rate of facial hairiness appears to influence male attractiveness; the presence of a beard makes the male vulnerable in hand to hand fights, costly, so biologists have speculated that there must be other evolutionary benefits that outweigh that drawback. Excess testosterone evidenced by the beard may indicate mild immunosuppression, which may support spermatogenesis; the ancient Semitic civilization situated on the western, coastal part of the Fertile Crescent and centered on the coastline of modern Lebanon gave great attention to the hair and beard. Where the beard has a strong resemblance to that affected by the Assyrians, familiar to us from their sculptures, it is arranged in three, four, or five rows of small tight curls, extends from ear to ear around the cheeks and chin. Sometimes, however, in lieu of the many rows, we find one row only, the beard falling in tresses, which are curled at the extremity. There is no indication of the Phoenicians having cultivated mustachios.
Mesopotamian civilizations devoted great care to oiling and dressing their beards, using tongs and curling irons to create elaborate ringlets and tiered patterns. The highest ranking Ancient Egyptians grew hair on their chins, dyed or hennaed and sometimes plaited with interwoven gold thread. A metal false beard, or postiche, a sign of sovereignty, was worn by queens and kings; this was held in place by a ribbon tied over the head and attached to a gold chin strap, a fashion existing from about 3000 to 1580 BC. In ancient India, the beard was allowed to grow a symbol of dignity and of wisdom; the nations in the east treated their beards with great care and veneration, the punishment for licentiousness and adultery was to have the beard of the offending parties publicly cut off. They had such a sacred regard for the preservation of their beards that a man might pledge it for the payment of a debt. Confucius held that the human body was a gift from one's parents to which no alterations should be made.
Aside from abstaining from body modifications such as tattoos, Confucians were discouraged from cutting their hair, finger nails or beards. To what extent people could comply with this ideal depended on their profession. Most of the clay soldiers in the Terracotta Army have mustasches or goatees but shaved cheeks, indicating that this was the fashion of the Qin dynasty; the Iranians were fond of long beards, all the Iranian kings had a beard. In Travels by Adam Olearius, a King of Iran commands his steward's head to be cut off, on its being brought to him, remarks, "what a pity it was, that a man possessing such fine mustachios, should have been executed." Men in the Achaemenid era wore long beards, with warriors adorning theirs with jewelry. Men commonly wore beards during the Safavid and Qajar eras; the ancient Greeks regarded the beard as a sign of virility. It was only shaven as a sign of mourning, though in this case it was instead left untrimmed. A smooth face was regarded as a sign of effem
The antitragus is a feature of mammalian ear anatomy. In humans, it is a small tubercle on the visible part of the ear; the antitragus is located just above the earlobe and points anteriorly. It is separated from the tragus by the intertragic notch; the antitragicus muscle, an intrinsic muscle of the ear, arises from the outer part of the antitragus. The antitragus can be most notably bats. Antitragus piercing This article incorporates text in the public domain from page 1034 of the 20th edition of Gray's Anatomy Anatomy photo:30:01-0105 at the SUNY Downstate Medical Center lesson3 at The Anatomy Lesson by Wesley Norman Diagram at bodymodforums.com
Echolocation called bio sonar, is the biological sonar used by several species of animal. Echolocating animals emit calls out to the environment and listen to the echoes of those calls that return from various objects near them, they use these echoes to identify the objects. Echolocation is used for foraging in various environments. Echolocating animals include a few birds; the term echolocation was coined by the American zoologist Donald Griffin, whose work with Robert Galambos was the first to convincingly demonstrate its existence in bats in 1938. As Griffin described in his book, the 18th century Italian scientist Lazzaro Spallanzani had, by means of a series of elaborate experiments, concluded that when bats fly at night, they rely on some sense besides vision, but he did not discover that the other sense was hearing; the Swiss physician and naturalist Louis Jurine repeated Spallanzani's experiments, concluded that when bats hunt at night, they rely on hearing. In 1908, Walter Louis Hahn confirmed Jurine's findings.
In 1912, the inventor Hiram Maxim independently proposed that bats used sound below the human auditory range to avoid obstacles. In 1920, the English physiologist Hamilton Hartridge proposed instead that bats used frequencies above the range of human hearing. Echolocation in odontocetes was not properly described until two decades after Griffin and Galambos' work, by Schevill and McBride in 1956. However, in 1953, Jacques Yves Cousteau suggested in his first book, The Silent World that porpoises had something like sonar, judging by their navigational abilities. Echolocation is the same as active sonar, using sounds made by the animal itself. Ranging is done by measuring the time delay between the animal's own sound emission and any echoes that return from the environment; the relative intensity of sound received at each ear as well as the time delay between arrival at the two ears provide information about the horizontal angle from which the reflected sound waves arrive. Unlike some human-made sonars that rely on many narrow beams and many receivers to localize a target, animal echolocation has only one transmitter and two receivers positioned apart.
The echoes returning to the ears arrive at different times and at different loudness levels, depending on the position of the object generating the echoes. The time and loudness differences are used by the animals to perceive direction. With echolocation, the bat or other animal can see not only where it is going but how big another animal is, what kind of animal it is, other features.. At the most basic level, echolocation is based on the neural anatomy of auditory brain circuitry. In essence, ascending brain pathways in the brain stem allow the brain to calculate the difference between the two ears to small fractions of a second. Microbats use echolocation to navigate and forage in total darkness, they emerge from their roosts in caves, attics, or trees at dusk and hunt for insects into the night. Their use of echolocation allows them to occupy a niche where there are many insects, less competition for food, fewer species that may prey on the bats themselves. Microbats generate ultrasound via the larynx and emit the sound through the open mouth or, much more the nose.
The latter is most pronounced in the horseshoe bats. Microbat calls range in frequency from 14,000 to well over 100,000 Hz beyond the range of the human ear. Bats may estimate the elevation of targets by interpreting the interference patterns caused by the echoes reflecting from the tragus, a flap of skin in the external ear. There are two hypotheses about the evolution of echolocation in bats; the first suggests that laryngeal echolocation evolved twice in Chiroptera, once in the Yangochiroptera and once in the horseshoe bats. The second proposes that laryngeal echolocation had a single origin in Chiroptera, was subsequently lost in the family Pteropodidae, evolved as a system of tongue-clicking in the genus Rousettus. Individual bat species echolocate within specific frequency ranges that suit their environment and prey types; this has sometimes been used by researchers to identify bats flying in an area by recording their calls with ultrasonic recorders known as "bat detectors". However echolocation calls are not always species specific and some bats overlap in the type of calls they use so recordings of echolocation calls cannot be used to identify all bats.
In recent years researchers in several countries have developed "bat call libraries" that contain recordings of local bat species that have been identified known as "reference calls" to assist with identification. Since the 1970s there has been an ongoing controversy among researchers as to whether bats use a form of processing known from radar termed coherent cross-correlation. Coherence means that the phase of the echolocation signals is used by the bats, while cross-correlation just implies that the outgoing signal is compared with the returning echoes in a running process. Today most – but not all – researchers believe that they use cross-correlation, but in an incoherent form, term