The primary visual cortex is the most well-studied visual area in the brain. It is the part of the cerebral cortex that is responsible for processing visual stimuli. It is the simplest, earliest cortical visual area. It is highly specialized for processing information about static and moving objects and is excellent in pattern recognition. The functionally defined primary visual cortex is approximately equivalent to the anatomically defined striate cortex. The name "striate cortex" is derived from the stria of Gennari ...

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Visual cortex, Visual cortex - Primary visual cortex V1, Visual cortex - Function, Visual cortex - Current research, Visual cortex - V2, Visual cortex - V3, Visual cortex - V4, Visual cortex - V5

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Three groups of animals, with some exceptions, have notably complex brains: the arthropods (insects and crustaceans), the cephalopods (octopuses, squid, and similar mollusks), and the craniates (vertebrates)[6]. The brain of arthropods and cephalopods arises from twin parallel nerve cords that extend through the body of the animal. In arthropods, the brain consists of a central brain with three divisions and large optical lobes behind each eye for visual processing^{See also:}

Brain, Brain - Mind and brain, Brain - History, Brain - Modern neuroscience, Brain - Comparative anatomy, Brain - Invertebrates, Brain - Vertebrates, Brain - Humans, Brain - Neurobiology, Brain - Histology, Brain - Function, Brain - Brain pathology, Brain - The study of the brain, Brain - Fields of study, Brain - Methods of observation, Brain - Other matters, Brain - Brain as food

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In the human brain, the central sulcus separates the frontal lobe from the parietal lobe along the top of each cerebral cortex. The lateral sulcus separates the inferior frontal gyrus of lower frontal lobes from the temporal lobes. The frontal lobe can be divided into a lateral, polar (frontalmost), orbital (above the orbit; also called basal), and medial part. Each of these parts consists of particular gyri: Lateral part: Precentral gyrus, lateral part of the superior frontal gyrus, middle frontal gyrus, inferior frontal ...

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Frontal lobe, Frontal lobe - Anatomy, Frontal lobe - Function, Frontal lobe - Psychosurgery

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It consists of five segments: a body, two greater cornua, and two lesser cornua. Hyoid bone - The body or basihyal. The body (corpus oss. hyoidei) or central part is of a quadrilateral form. Its anterior surface [Fig. 1] is convex and directed forward and upward. It is crossed in its upper half by a well-marked transverse ridge with a slight downward convexity, and in many cases a vertical median ridge divides it into two lateral halves. The portion of the vertical ridge above ...

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Hyoid bone, Hyoid bone - Segments, Hyoid bone - The body or basihyal, Hyoid bone - The greater cornua or thyrohyals, Hyoid bone - The lesser cornua or ceratohyals, Hyoid bone - Ossification, Hyoid bone - Fracture

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Termites do not physically resemble ants; their "white ant" name is probably due to their similar size and social habits. Termites have biting mouthparts and their soft bodies are small, rarely over 10 mm in length. They typically inhabit dark nests and tunnels, only venturing out when the winged alates emerge to leave their parent colony, when constructing shelter or, in the case of grass-eaters, when harvesting grass stems. The bodies of flying individuals are dark, while termites which remain in the nest are whitish with only their ...

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Termite, Termite - Appearance and Morphological Behaviour, Termite - Social Structure, Termite - Diet, Termite - Mounds, Termite - Human Interaction, Termite - Ecology and Natural History, Termite - Relationships and Evolutionary History

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The female clitoris corresponds to homologous parts of the male penis, i.e., embryologically it comes from the same tissue that forms the penis. The trigger for forming a penis instead of a clitoris is the action of testosterone in utero. The organ is formed out of corpus cavernosum, a rich collection of capillary tissue with a substantial presence of nerve tissue. It is particularly well-suited for sexual stimulation. The outside portion of the clitoris, the clitoral glans, is entirely or partially covered by the ...

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Clitoris, Clitoris - Development and formation, Clitoris - Recognition of existence, Clitoris - Body modification, Clitoris - Popular culture

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Problems with dentures include the fact that patients are not used to having something in their mouth that is not food. The brain senses this appliance as "food" and sends messages to the salivary glands to produce more saliva and to secrete it at a higher rate. New dentures will also be the inevitable cause of sore spots as they rub and press on the mucosa. A few denture adjustments for the weeks following insertion of the dentures can take care of this issue. Another problem with dentures is keeping them in place. There are three rules governing the existance of removable oral applianc ...

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Dentures, Dentures - Problems associated with Complete Dentures, Dentures - Mini implants

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The front (ventrum) of the head, where the eyes and ears and mouth are located, is called the face. The area above the eyes is called the forehead (the front of the head). Below the mouth is the chin. Younger aged humans and some older humans heads have a continuing growing layer of hair covering the head. Most females of the human race do not lose this covering during the aging process, however some males can lose their head hair as they grow older. In most complex animals the head is joined to the rest of the body by the neck. Head - Hu ...

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Head, Head - Anatomy, Head - Human head anatomy, Head - The face, Head - Cultural import, Head - Clothing, Head - Pseudoscientific study of the human head

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The coccyx is formed of four rudimentary vertebrae; the number may be as high as five or as low as three. It articulates superiorly with the sacrum. In each of the first three segments may be traced a rudimentary body and articular and transverse processes; the last piece (sometimes the third) is a mere nodule of bone. All the segments are destitute of pedicles, laminae, and spinous processes. The first is the largest; it resembles the lowest sacral vertebra, and often exists as a separate piece; the last three diminish in size from above downward, and are usually fused with one another. ...

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Coccyx, Coccyx - Function, Coccyx - Structure, Coccyx - Surfaces, Coccyx - Borders, Coccyx - Base, Coccyx - Apex, Coccyx - Pathology

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There are several morphological characteristics that distinguish acanthocephalans from other phyla of parasitic worms. Acanthocephala - Digestion. Acanthocephalans lack a mouth or alimentary canal. This is a feature they share with the cestoda (tapeworms), although the two groups are not related. Adult stages live in the intestines of their host and uptake nutrients which have been digested by the host, directly, through their body s ...

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Acanthocephala, Acanthocephala - Morphological Characteristics, Acanthocephala - Digestion, Acanthocephala - Proboscis, Acanthocephala - Phylogenetic Relationships, Acanthocephala - Size, Acanthocephala - Skin, Acanthocephala - Nervous System, Acanthocephala - Sex, Acanthocephala - Other Features, Acanthocephala - Life Cycles, Acanthocephala - General Patterns, Acanthocephala - An example - Polymorphus spp.

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Birds are generally considered to have evolved from theropod dinosaurs. Specifically, birds are members of Maniraptora, a group of theropods which includes dromaeosaurs and oviraptorids, among others. As more non-avian theropods that are closely related to birds are discovered, the formerly clear distinction between non-birds and birds becomes less so. Recent discoveries in North-east China (Liaoning Province) demonstrating that many small theropod dinosaurs had feat ...

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Bird, Bird - High-level taxonomy, Bird - Bird orders, Bird - Evolution, Bird - Reproduction, Bird - Mating systems and parental care, Bird - Respiration, Bird - Other anatomy, Bird - Birds and humans, Bird - Trivia

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facial expression: auricularis anterior - buccinator - corrugator supercilii - depressor anguli oris - depressor labii inferioris - depressor septi nasi - levator anguli oris - levator labii superioris - levator labii superioris alaeque nasi - levator palpebrae superioris - mentalis - nasalis - occipitofrontalis (occipitalis, frontalis) - orbicularis oculi - orbicularis oris - platysma - procerus - risorius - zygomatic (major, minor) mastication: ...

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List of muscles of the human body, List of muscles of the human body - The muscles of the head, List of muscles of the human body - The muscles of the anterolateral region of the neck, List of muscles of the human body - The muscles of the trunk, List of muscles of the human body - The muscles of the upper limb, List of muscles of the human body - The muscles of the lower limb, List of muscles of the human body - Sources

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The adult human liver normally weighs between 1.0 - 2.5 kilograms, and is a soft, pinkish-brown "boomerang shaped" organ. It is the second largest organ (the largest organ being the skin) Its anatomical postion in the body is : immediately under the diaphragm on the right side of the upper abdomen. The liver lies on the right of the stomach and makes a kind of bed for the gallbladder (which stores bile). The liver is supplied by two major blood vessels on its right lobe: the hepatic artery and the portal vein. The hepatic artery ...

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Liver, Liver - Anatomy, Liver - Surface anatomy, Liver - Functional anatomy, Liver - Physiology, Liver - Diseases of the liver, Liver - Liver transplantation, Liver - Development, Liver - Fetal blood supply, Liver - Analogous organs, Liver - Liver as food, Liver - Cultural allusions

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HEAD: ARTERIES: carotid - common carotid - internal carotid (ophthalmic, retinal, anterior cerebral, middle cerebral, posterior communicating) - external carotid (facial, maxillary, superficial temporal artery) - posterior cerebral - anterior communicating - posterior inferior cerebellar - basilar - circle of Willis - middle meningeal | VEINS: jugular - vein of Galen ARMS: ARTERIES: axillary (superior thoracic, thoracoacromial, lateral thoracic, subscapular, anterior circumflex humeral, posterior circumflex ...

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Brachial artery, Brachial artery - Branches, Brachial artery - External link

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The branches of the ophthalmic artery are often subdivided into an orbital group and an ocular group [1]. Ophthalmic artery - Orbital group. The orbital group, distributing vessels to the orbit and surrounding parts, includes: Lacrimal artery Supraorbital artery Posterior ethmoidal artery Anterior ethmoidal artery Internal palpebral artery Supratrochlear artery, also known as the frontal artery Dorsal nasal artery See also:

Ophthalmic artery, Ophthalmic artery - Branches, Ophthalmic artery - Orbital group, Ophthalmic artery - Ocular group, Ophthalmic artery - Structures supplied, Ophthalmic artery - Occlusion

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The precentral gyrus lies in front of the postcentral gyrus - mostly on the lateral (convex) side of the cerebral hemispheres - from which it is separated by the central sulcus. Its anterior border is represented by the precentral sulcus, while inferiorly it borders to the lateral fissure (Sylvian fissure). Medially, it is contiguous with the paracentral lobule. The internal pyramidal layer (layer V) of the precentral cortex contains giant (70-100 micrometers) pyramidal neurons (a.k.a. Betz cells), w ...

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Primary motor cortex, Primary motor cortex - Anatomy, Primary motor cortex - Function

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Although most male birds have no external sex organs, the male does have two testes which become hundreds of times larger during the breeding season to produce sperm. The female's ovaries also become larger, although only the left ovary actually functions. In the males of species without a phallus (see below), sperm is stored within the proctodeum compartment within the cloaca prior to copulation. During copulation, the female moves her tail to the side and the male either mounts the female from behind or moves very close to her. He m ...

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Bird, Bird - High-level taxonomy, Bird - Bird orders, Bird - Evolution, Bird - Reproduction, Bird - Mating systems and parental care, Bird - Respiration, Bird - Other anatomy, Bird - Birds and humans, Bird - Trivia

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Birds ventilate their lungs by means of crosscurrent flow: the air flows at a 90° angle to the flow of blood in the lungs' capillaries. In addition to the lungs themselves, birds have posterior and anterior air sacs (typically nine) which control air flow through the lungs, but do not play a direct role in gas exchange. There are three parts involved in respiration: the anterior air sacs (interclavicular, cervicals, and anterior thoracics), the lungs, and the posterior air sacs (posteri ...

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Bird, Bird - High-level taxonomy, Bird - Bird orders, Bird - Evolution, Bird - Reproduction, Bird - Mating systems and parental care, Bird - Respiration, Bird - Other anatomy, Bird - Birds and humans, Bird - Trivia

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Birds form a class, whose scientific name is Aves. The founding species of class Aves probably lived in the Jurassic period. According to the most recent consensus, Class Aves and a sister group, the family Crocodylidae, together form a group of unnamed rank, the Archosauria. The class of birds separated early into two superorders, the Paleognathae (mostly flightless birds like ostriches), and the wildly div ...

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Bird, Bird - High-level taxonomy, Bird - Bird orders, Bird - Evolution, Bird - Reproduction, Bird - Mating systems and parental care, Bird - Respiration, Bird - Other anatomy, Bird - Birds and humans, Bird - Trivia

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Birds are an important food source for humans. The most commonly eaten species is the domestic chicken and its eggs, although geese, pheasants, turkeys, and ducks are also widely eaten. Other birds that have been utilized for food include emus, ostriches, pigeons, grouse, quails, doves, woodcocks, songbirds, and others, including small passerines such as finches. At one time swans and flamingos were delicacies of the rich and powerful, al ...

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Bird, Bird - High-level taxonomy, Bird - Bird orders, Bird - Evolution, Bird - Reproduction, Bird - Mating systems and parental care, Bird - Respiration, Bird - Other anatomy, Bird - Birds and humans, Bird - Trivia

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This is a list of the taxonomic orders in the class Aves. The list of birds gives a more detailed summary, including families. Struthioniformes, Ostrich, emus, kiwis, and allies Tinamiformes, tinamous Anseriformes, waterfowl Galliformes, fowl Sphenisciformes, penguins Gaviiformes, loons Podicipediformes, grebes Procellariiformes, albatrosses, petrels, and allies Pelecaniformes, pelicans and allies Ciconiiformes, storks and allies Phoenicopt ...

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Bird, Bird - High-level taxonomy, Bird - Bird orders, Bird - Evolution, Bird - Reproduction, Bird - Mating systems and parental care, Bird - Respiration, Bird - Other anatomy, Bird - Birds and humans, Bird - Trivia

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Sources for this section include: Gowaty, Patricia Adair: Male Parental Care and Apparent Monogamy among Eastern Bluebirds (Sialia Sialis). The American Naturalist 121(2): 149-160 (1983). Ketterson, Ellen D. and Nolan, Val: Male Parental Behavior in Birds. Annual Review of Ecology and Systematics 25: 601-28 (1994). Zeveloff, Samuel and Boyce, Mark: Parental Investment and Mating Systems i ...

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Bird, Bird - High-level taxonomy, Bird - Bird orders, Bird - Evolution, Bird - Reproduction, Bird - Mating systems and parental care, Bird - Respiration, Bird - Other anatomy, Bird - Birds and humans, Bird - Trivia

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