104-464: Physiology ( / ˌ f ɪ z i ˈ ɒ l ə dʒ i / ; from Ancient Greek φύσις ( phúsis ) 'nature, origin' and -λογία ( -logía ) 'study of') is the scientific study of functions and mechanisms in a living system . As a subdiscipline of biology , physiology focuses on how organisms , organ systems , individual organs , cells , and biomolecules carry out chemical and physical functions in
208-444: A head , hair , neck , torso (which includes the thorax and abdomen ), genitals , arms , hands , legs , and feet . The internal human body includes organs, teeth , bones , muscle , tendons , ligaments , blood vessels and blood , lymphatic vessels and lymph . The study of the human body includes anatomy , physiology , histology and embryology . The body varies anatomically in known ways. Physiology focuses on
312-543: A pitch accent . In Modern Greek, all vowels and consonants are short. Many vowels and diphthongs once pronounced distinctly are pronounced as /i/ ( iotacism ). Some of the stops and glides in diphthongs have become fricatives , and the pitch accent has changed to a stress accent . Many of the changes took place in the Koine Greek period. The writing system of Modern Greek, however, does not reflect all pronunciation changes. The examples below represent Attic Greek in
416-649: A bell and visual stimuli. In the 19th century, physiological knowledge began to accumulate at a rapid rate, in particular with the 1838 appearance of the Cell theory of Matthias Schleiden and Theodor Schwann . It radically stated that organisms are made up of units called cells. Claude Bernard 's (1813–1878) further discoveries ultimately led to his concept of milieu interieur (internal environment), which would later be taken up and championed as " homeostasis " by American physiologist Walter B. Cannon in 1929. By homeostasis, Cannon meant "the maintenance of steady states in
520-519: A cell . Here, parts of DNA are copied and sent to the body of the cell via RNA . The RNA is then used to create proteins , which form the basis for cells, their activity, and their products. Proteins dictate cell function and gene expression, a cell is able to self-regulate by the amount of proteins produced. However, not all cells have DNA; some cells such as mature red blood cells lose their nucleus as they mature. The body consists of many different types of tissue , defined as cells that act with
624-498: A distinct subdiscipline. In 1920, August Krogh won the Nobel Prize for discovering how, in capillaries, blood flow is regulated. In 1954, Andrew Huxley and Hugh Huxley, alongside their research team, discovered the sliding filaments in skeletal muscle , known today as the sliding filament theory. Recently, there have been intense debates about the vitality of physiology as a discipline (Is it dead or alive?). If physiology
728-477: A lack of contemporaneous evidence. Several theories exist about what Hellenic dialect groups may have existed between the divergence of early Greek-like speech from the common Proto-Indo-European language and the Classical period. They have the same general outline but differ in some of the detail. The only attested dialect from this period is Mycenaean Greek , but its relationship to the historical dialects and
832-419: A lesser degree. Pamphylian Greek , spoken in a small area on the southwestern coast of Anatolia and little preserved in inscriptions, may be either a fifth major dialect group, or it is Mycenaean Greek overlaid by Doric, with a non-Greek native influence. Regarding the speech of the ancient Macedonians diverse theories have been put forward, but the epigraphic activity and the archaeological discoveries in
936-614: A living system. According to the classes of organisms , the field can be divided into medical physiology , animal physiology , plant physiology , cell physiology , and comparative physiology . Central to physiological functioning are biophysical and biochemical processes, homeostatic control mechanisms, and communication between cells. Physiological state is the condition of normal function. In contrast, pathological state refers to abnormal conditions , including human diseases . The Nobel Prize in Physiology or Medicine
1040-456: A medical field originates in classical Greece , at the time of Hippocrates (late 5th century BC). Outside of Western tradition, early forms of physiology or anatomy can be reconstructed as having been present at around the same time in China , India and elsewhere. Hippocrates incorporated the theory of humorism , which consisted of four basic substances: earth, water, air and fire. Each substance
1144-420: A number of body cavities , separated areas which house different organ systems. The brain and central nervous system reside in an area protected from the rest of the body by the blood brain barrier . The lungs sit in the pleural cavity . The intestines , liver , and spleen sit in the abdominal cavity . Height, weight, shape and other body proportions vary individually and with age and sex. Body shape
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#17327650635861248-399: A number of sexually transmitted infections including syphilis , HIV , chlamydia , HPV and genital warts . Cancer can affect most parts of the reproductive system including the penis , testicles , prostate , ovaries , cervix , vagina , fallopian , uterus and vulva . The respiratory system consists of the nose, nasopharynx , trachea , and lungs . It brings oxygen from
1352-550: A prefix /e-/, called the augment . This was probably originally a separate word, meaning something like "then", added because tenses in PIE had primarily aspectual meaning. The augment is added to the indicative of the aorist, imperfect, and pluperfect, but not to any of the other forms of the aorist (no other forms of the imperfect and pluperfect exist). The two kinds of augment in Greek are syllabic and quantitative. The syllabic augment
1456-608: A separate historical stage, though its earliest form closely resembles Attic Greek , and its latest form approaches Medieval Greek . There were several regional dialects of Ancient Greek; Attic Greek developed into Koine. Ancient Greek was a pluricentric language , divided into many dialects. The main dialect groups are Attic and Ionic , Aeolic , Arcadocypriot , and Doric , many of them with several subdivisions. Some dialects are found in standardized literary forms in literature , while others are attested only in inscriptions. There are also several historical forms. Homeric Greek
1560-505: A specialised function. The study of tissues is called histology and is often done with a microscope . The body consists of four main types of tissues. These are lining cells ( epithelia ), connective tissue , nerve tissue and muscle tissue . Cells that line surfaces exposed to the outside world or gastrointestinal tract ( epithelia ) or internal cavities ( endothelium ) come in numerous shapes and forms – from single layers of flat cells , to cells with small beating hair-like cilia in
1664-630: A standard subject of study in educational institutions of the Western world since the Renaissance . This article primarily contains information about the Epic and Classical periods of the language, which are the best-attested periods and considered most typical of Ancient Greek. From the Hellenistic period ( c. 300 BC ), Ancient Greek was followed by Koine Greek , which is regarded as
1768-427: A unified science of life based on the cell actions, later renamed in the 20th century as cell biology . In the 20th century, biologists became interested in how organisms other than human beings function, eventually spawning the fields of comparative physiology and ecophysiology . Major figures in these fields include Knut Schmidt-Nielsen and George Bartholomew . Most recently, evolutionary physiology has become
1872-510: A vowel or /n s r/ ; final stops were lost, as in γάλα "milk", compared with γάλακτος "of milk" (genitive). Ancient Greek of the classical period also differed in both the inventory and distribution of original PIE phonemes due to numerous sound changes, notably the following: The pronunciation of Ancient Greek was very different from that of Modern Greek . Ancient Greek had long and short vowels ; many diphthongs ; double and single consonants; voiced, voiceless, and aspirated stops ; and
1976-442: Is swallowed , and moves through the esophagus to the stomach . In the stomach, food is mixed with gastric acids to allow the extraction of nutrients . What is left is called chyme ; this then moves into the small intestine , which absorbs the nutrients and water from the chyme. What remains passes on to the large intestine , where it is dried to form feces ; these are then stored in the rectum until they are expelled through
2080-433: Is a common disease in which one or more stones form in the gallbladder or biliary tract . Most people are asymptomatic but if a stone blocks the biliary tract, it causes a gallbladder attack , symptoms may include sudden pain in the upper right abdomen or center of the abdomen. Nausea and vomiting may also occur. Typical treatment is removal of the gallbladder through a procedure called a cholecystectomy . Having gallstones
2184-570: Is a literary form of Archaic Greek (derived primarily from Ionic and Aeolic) used in the epic poems , the Iliad and the Odyssey , and in later poems by other authors. Homeric Greek had significant differences in grammar and pronunciation from Classical Attic and other Classical-era dialects. The origins, early form and development of the Hellenic language family are not well understood because of
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#17327650635862288-444: Is a risk factor for gallbladder cancer , which although quite uncommon, is rapidly fatal if not diagnosed early. The circulatory system consists of the heart and blood vessels ( arteries , veins and capillaries ). The heart propels the circulation of the blood, which serves as a "transportation system" to transfer oxygen , fuel, nutrients, waste products, immune cells and signaling molecules (i.e. hormones ) from one part of
2392-423: Is achieved through communication that occurs in a variety of ways, both electrical and chemical. Changes in physiology can impact the mental functions of individuals. Examples of this would be the effects of certain medications or toxic levels of substances. Change in behavior as a result of these substances is often used to assess the health of individuals. Much of the foundation of knowledge in human physiology
2496-418: Is added to stems beginning with consonants, and simply prefixes e (stems beginning with r , however, add er ). The quantitative augment is added to stems beginning with vowels, and involves lengthening the vowel: Some verbs augment irregularly; the most common variation is e → ei . The irregularity can be explained diachronically by the loss of s between vowels, or that of the letter w , which affected
2600-483: Is awarded by the Royal Swedish Academy of Sciences for exceptional scientific achievements in physiology related to the field of medicine . Because physiology focuses on the functions and mechanisms of living organisms at all levels, from the molecular and cellular level to the level of whole organisms and populations, its foundations span a range of key disciplines: There are many ways to categorize
2704-415: Is brought by the ureters from the kidneys down to the bladder . The smooth muscle lining the ureter walls continuously tighten and relax through a process called peristalsis to force urine away from the kidneys and down into the bladder. Small amounts of urine are released into the bladder every 10–15 seconds. The bladder is a hollow balloon shaped organ located in the pelvis . It stores urine until
2808-666: Is called 'East Greek'. Arcadocypriot apparently descended more closely from the Mycenaean Greek of the Bronze Age. Boeotian Greek had come under a strong Northwest Greek influence, and can in some respects be considered a transitional dialect, as exemplified in the poems of the Boeotian poet Pindar who wrote in Doric with a small Aeolic admixture. Thessalian likewise had come under Northwest Greek influence, though to
2912-448: Is considered by some linguists to have been closely related to Greek . Among Indo-European branches with living descendants, Greek is often argued to have the closest genetic ties with Armenian (see also Graeco-Armenian ) and Indo-Iranian languages (see Graeco-Aryan ). Ancient Greek differs from Proto-Indo-European (PIE) and other Indo-European languages in certain ways. In phonotactics , ancient Greek words could end only in
3016-399: Is essential for diagnosing and treating health conditions and promoting overall wellbeing. It seeks to understand the mechanisms that work to keep the human body alive and functioning, through scientific enquiry into the nature of mechanical, physical, and biochemical functions of humans, their organs, and the cells of which they are composed. The principal level of focus of physiology is at
3120-419: Is influenced by the distribution of bones, muscle and fat tissue . Human physiology is the study of how the human body functions. This includes the mechanical, physical, bioelectrical , and biochemical functions of humans in good health, from organs to the cells of which they are composed. The human body consists of many interacting systems of organs. These interact to maintain homeostasis , keeping
3224-469: Is known for having a corresponding humor: black bile, phlegm, blood, and yellow bile, respectively. Hippocrates also noted some emotional connections to the four humors, on which Galen would later expand. The critical thinking of Aristotle and his emphasis on the relationship between structure and function marked the beginning of physiology in Ancient Greece . Like Hippocrates , Aristotle took to
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3328-509: Is mostly responsible for gathering information with sensory neurons and directing body movements with motor neurons . From a functional perspective, the nervous system is again typically divided into two component parts: the somatic nervous system (SNS) and the autonomic nervous system (ANS). The SNS is involved in voluntary functions like speaking and sensory processes . The ANS is involved in involuntary processes, such as digestion and regulating blood pressure . The nervous system
3432-575: Is perhaps less visible nowadays than during the golden age of the 19th century, it is in large part because the field has given birth to some of the most active domains of today's biological sciences, such as neuroscience , endocrinology , and immunology . Furthermore, physiology is still often seen as an integrative discipline, which can put together into a coherent framework data coming from various different domains. Initially, women were largely excluded from official involvement in any physiological society. The American Physiological Society , for example,
3536-405: Is similar to the circulatory system in terms of both its structure and its most basic function, to carry a body fluid. The musculoskeletal system consists of the human skeleton (which includes bones , ligaments , tendons , joints and cartilage ) and attached muscles . It gives the body basic structure and the ability for movement. In addition to their structural role, the larger bones in
3640-430: Is subject to many different diseases. In epilepsy , abnormal electrical activity in the brain can cause seizures . In multiple sclerosis , the immune system attacks the nerve linings , damaging the nerves' ability to transmit signals. Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig 's disease, is a motor neuron disease which gradually reduces movement in patients. There are also many other diseases of
3744-425: Is the organ of thought , emotion, memory , and sensory processing ; it serves many aspects of communication and controls various systems and functions. The special senses consist of vision , hearing , taste , and smell . The eyes , ears , tongue , and nose gather information about the body's environment. From a structural perspective, the nervous system is typically subdivided into two component parts:
3848-442: Is the study of the shape and form of the human body. The human body has four limbs (two arms and two legs), a head and a neck , which connect to the torso . The body's shape is determined by a strong skeleton made of bone and cartilage , surrounded by fat ( adipose tissue ), muscle, connective tissue , organs, and other structures. The spine at the back of the skeleton contains the flexible vertebral column , which surrounds
3952-433: Is variable in shape and size. It stores bile before it is released into the small intestine via the common bile duct to help with digestion of fats . It receives bile from the liver via the cystic duct , which connects to the common hepatic duct to form the common bile duct . The gallbladder gets its blood supply from the cystic artery , which in most people, emerges from the right hepatic artery . Gallstones
4056-759: The Greek region of Macedonia during the last decades has brought to light documents, among which the first texts written in Macedonian , such as the Pella curse tablet , as Hatzopoulos and other scholars note. Based on the conclusions drawn by several studies and findings such as Pella curse tablet , Emilio Crespo and other scholars suggest that ancient Macedonian was a Northwest Doric dialect , which shares isoglosses with its neighboring Thessalian dialects spoken in northeastern Thessaly . Some have also suggested an Aeolic Greek classification. The Lesbian dialect
4160-441: The anus . The endocrine system consists of the principal endocrine glands : the pituitary , thyroid , adrenals , pancreas , parathyroids , and gonads , but nearly all organs and tissues produce specific endocrine hormones as well. The endocrine hormones serve as signals from one body system to another regarding an enormous array of conditions, resulting in variety of changes of function. The immune system consists of
4264-520: The central nervous system (CNS), composed of the brain and the spinal cord ; and the peripheral nervous system (PNS), composed of the nerves and ganglia outside the brain and spinal cord. The CNS is mostly responsible for organizing motion , processing sensory information , thought, memory, cognition and other such functions. It remains a matter of some debate whether the CNS directly gives rise to consciousness . The peripheral nervous system (PNS)
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4368-468: The heart , lungs and liver . Many organs reside within cavities within the body. These cavities include the abdomen (which contains the stomach, for example) and pleura , which contains the lungs. The heart is an organ located in the thoracic cavity between the lungs and slightly to the left. It is surrounded by the pericardium , which holds it in place in the mediastinum and serves to protect it from blunt trauma, infection and help lubricate
4472-441: The kidneys filter the blood through their respective nephrons , removing waste products like urea , creatinine and maintaining the proper balance of electrolytes and turning the waste products into urine by combining them with water from the blood. The kidneys filter about 150 quarts (170 liters) of blood daily, but most of it is returned to the blood stream with only 1-2 quarts (1-2 liters) ending up as urine. The urine
4576-456: The ovary of a female is penetrated by sperm . The egg then lodges in the uterus , where an embryo and later fetus develop until birth . Growth and development occur after birth, and include both physical and psychological development, influenced by genetic, hormonal, environmental and other factors. Development and growth continue throughout life, through childhood , adolescence , and through adulthood to old age , and are referred to as
4680-501: The present , future , and imperfect are imperfective in aspect; the aorist , present perfect , pluperfect and future perfect are perfective in aspect. Most tenses display all four moods and three voices, although there is no future subjunctive or imperative. Also, there is no imperfect subjunctive, optative or imperative. The infinitives and participles correspond to the finite combinations of tense, aspect, and voice. The indicative of past tenses adds (conceptually, at least)
4784-407: The sinoatrial node traveling through the atria causing them to pump blood into the ventricles . It then travels to the atrioventricular node , which makes the signal slow down slightly allowing the ventricles to fill with blood before pumping it out and starting the cycle over again. Coronary artery disease is the leading cause of death worldwide , making up 16% of all deaths. It is caused by
4888-400: The spinal cord , which is a collection of nerve fibres connecting the brain to the rest of the body. Nerves connect the spinal cord and brain to the rest of the body. All major bones, muscles, and nerves in the body are named, with the exception of anatomical variations such as sesamoid bones and accessory muscles . Blood vessels carry blood throughout the body, which moves because of
4992-421: The spleen and bone marrow . The digestive system consists of the mouth including the tongue and teeth , esophagus , stomach , ( gastrointestinal tract , small and large intestines , and rectum ), as well as the liver , pancreas , gallbladder , and salivary glands . It converts food into small, nutritional, non-toxic molecules for distribution and absorption into the body. These molecules take
5096-432: The testicles . The testicle is the gonad , the sex gland that produces the sperm cells . Unlike the egg cells in the female, sperm cells are produced throughout life. Other internal sex organs are the epididymides , vasa deferentia , and some accessory glands . Diseases that affect the reproductive system include polycystic ovary syndrome , a number of disorders of the testicles including testicular torsion , and
5200-427: The uterus , and the cervix . At birth there are about 70,000 immature egg cells that degenerate until at puberty there are around 40,000. No more egg cells are produced. Hormones stimulate the beginning of menstruation, and the ongoing menstrual cycles . The female external sex organs are the vulva ( labia , clitoris , and vestibule ). The male external genitalia include the penis and scrotum that contains
5304-441: The white blood cells , the thymus , lymph nodes and lymph channels, which are also part of the lymphatic system . The immune system provides a mechanism for the body to distinguish its own cells and tissues from outside cells and substances and to neutralize or destroy the latter by using specialized proteins such as antibodies , cytokines , and toll-like receptors , among many others. The integumentary system consists of
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#17327650635865408-1031: The 5th century BC. Ancient pronunciation cannot be reconstructed with certainty, but Greek from the period is well documented, and there is little disagreement among linguists as to the general nature of the sounds that the letters represent. /oː/ raised to [uː] , probably by the 4th century BC. Greek, like all of the older Indo-European languages , is highly inflected. It is highly archaic in its preservation of Proto-Indo-European forms. In ancient Greek, nouns (including proper nouns) have five cases ( nominative , genitive , dative , accusative , and vocative ), three genders ( masculine , feminine , and neuter ), and three numbers (singular, dual , and plural ). Verbs have four moods ( indicative , imperative , subjunctive , and optative ) and three voices (active, middle, and passive ), as well as three persons (first, second, and third) and various other forms. Verbs are conjugated through seven combinations of tenses and aspect (generally simply called "tenses"):
5512-495: The Archaic period of ancient Greek (see Homeric Greek for more details): Μῆνιν ἄειδε, θεά, Πηληϊάδεω Ἀχιλῆος οὐλομένην, ἣ μυρί' Ἀχαιοῖς ἄλγε' ἔθηκε, πολλὰς δ' ἰφθίμους ψυχὰς Ἄϊδι προΐαψεν ἡρώων, αὐτοὺς δὲ ἑλώρια τεῦχε κύνεσσιν οἰωνοῖσί τε πᾶσι· Διὸς δ' ἐτελείετο βουλή· ἐξ οὗ δὴ τὰ πρῶτα διαστήτην ἐρίσαντε Ἀτρεΐδης τε ἄναξ ἀνδρῶν καὶ δῖος Ἀχιλλεύς. The beginning of Apology by Plato exemplifies Attic Greek from
5616-668: The Classical period of ancient Greek. (The second line is the IPA , the third is transliterated into the Latin alphabet using a modern version of the Erasmian scheme .) Ὅτι [hóti Hóti μὲν men mèn ὑμεῖς, hyːmêːs hūmeîs, Human body The human body is the entire structure of a human being . It is composed of many different types of cells that together create tissues and subsequently organs and then organ systems . The external human body consists of
5720-436: The ages of 9 and 13 and is characterized by ovulation and menstruation ; the growth of secondary sex characteristics, such as growth of pubic and underarm hair , breast , uterine and vaginal growth, widening hips and increased height and weight, also occur during puberty. Male puberty sees the further development of the penis and testicles . The female inner sex organs are the two ovaries, their fallopian tubes ,
5824-435: The air and excretes carbon dioxide and water back into the air. First, air is pulled through the trachea into the lungs by the diaphragm pushing down, which creates a vacuum . Air is briefly stored inside small sacs known as alveoli (sing.: alveolus) before being expelled from the lungs when the diaphragm contracts again. Each alveolus is surrounded by capillaries carrying deoxygenated blood, which absorbs oxygen out of
5928-420: The air and into the bloodstream . For the respiratory system to function properly, there need to be as few impediments as possible to the movement of air within the lungs. Inflammation of the lungs and excess mucus are common sources of breathing difficulties. In asthma , the respiratory system is persistently inflamed, causing wheezing or shortness of breath . Pneumonia occurs through infection of
6032-400: The alveoli, and may be caused by tuberculosis . Emphysema , commonly a result of smoking , is caused by damage to connections between the alveoli. The urinary system consists of the two kidneys , two ureters , bladder , and urethra . It removes waste materials from the blood through urine, which carries a variety of waste molecules and excess ions and water out of the body. First,
6136-550: The aorist. Following Homer 's practice, the augment is sometimes not made in poetry , especially epic poetry. The augment sometimes substitutes for reduplication; see below. Almost all forms of the perfect, pluperfect, and future perfect reduplicate the initial syllable of the verb stem. (A few irregular forms of perfect do not reduplicate, whereas a handful of irregular aorists reduplicate.) The three types of reduplication are: Irregular duplication can be understood diachronically. For example, lambanō (root lab ) has
6240-419: The augment when it was word-initial. In verbs with a preposition as a prefix, the augment is placed not at the start of the word, but between the preposition and the original verb. For example, προσ(-)βάλλω (I attack) goes to προσ έ βαλoν in the aorist. However compound verbs consisting of a prefix that is not a preposition retain the augment at the start of the word: αὐτο(-)μολῶ goes to ηὐ τομόλησα in
6344-406: The beating of the heart . Venules and veins collect blood low in oxygen from tissues throughout the body. These collect in progressively larger veins until they reach the body's two largest veins, the superior and inferior vena cava , which drain blood into the right side of the heart. From here, the blood is pumped into the lungs where it receives oxygen and drains back into the left side of
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#17327650635866448-416: The blood . Santorio Santorio in 1610s was the first to use a device to measure the pulse rate (the pulsilogium ), and a thermoscope to measure temperature. In 1791 Luigi Galvani described the role of electricity in the nerves of dissected frogs. In 1811, César Julien Jean Legallois studied respiration in animal dissection and lesions and found the center of respiration in the medulla oblongata . In
6552-420: The body and the physiological processes through which they are regulated." In other words, the body's ability to regulate its internal environment. William Beaumont was the first American to utilize the practical application of physiology. Nineteenth-century physiologists such as Michael Foster , Max Verworn , and Alfred Binet , based on Haeckel 's ideas, elaborated what came to be called "general physiology",
6656-427: The body contain bone marrow , the site of production of blood cells. Also, all bones are major storage sites for calcium and phosphate . This system can be split up into the muscular system and the skeletal system . The nervous system consists of the body's neurons and glial cells, which together form the nerves , ganglia and gray matter , which in turn form the brain and related structures. The brain
6760-423: The body in a stable state with safe levels of substances such as sugar and oxygen in the blood. Each system contributes to homeostasis, of itself, other systems, and the entire body. Some combined systems are referred to by joint names. For example, the nervous system and the endocrine system operate together as the neuroendocrine system . The nervous system receives information from the body, and transmits this to
6864-441: The body to another. Paths of blood circulation within the human body can be divided into two circuits: the pulmonary circuit , which pumps blood to the lungs to receive oxygen and leave carbon dioxide , and the systemic circuit, which carries blood from the heart off to the rest of the body. The blood consists of fluid that carries cells in the circulation, including some that move from tissue to blood vessels and back, as well as
6968-558: The body. The adult male body is about 60% total body water content of some 42 litres (9.2 imp gal; 11 US gal). This is made up of about 19 litres (4.2 imp gal; 5.0 US gal) of extracellular fluid including about 3.2 litres (0.70 imp gal; 0.85 US gal) of blood plasma and about 8.4 litres (1.8 imp gal; 2.2 US gal) of interstitial fluid , and about 23 litres (5.1 imp gal; 6.1 US gal) of fluid inside cells. The content, acidity and composition of
7072-412: The brain signals it to relax the urinary sphincter and release the urine into the urethra starting urination . A normal bladder can hold up to 16 ounces (half a liter) for 3–5 hours comfortably. Numerous diseases affect the urinary system including kidney stones , which are formed when materials in the urine concentrate enough to form a solid mass, urinary tract infections , which are infections of
7176-463: The brain via nerve impulses and neurotransmitters . At the same time, the endocrine system releases hormones, such as to help regulate blood pressure and volume. Together, these systems regulate the internal environment of the body, maintaining blood flow, posture, energy supply, temperature, and acid balance ( pH ). Development of the human body is the process of growth to maturity. The process begins with fertilisation, where an egg released from
7280-481: The buildup of plaque in the coronary arteries supplying the heart, eventually the arteries may become so narrow that not enough blood is able to reach the myocardium , a condition known as myocardial infarction or heart attack , this can cause heart failure or cardiac arrest and eventually death. Risk factors for coronary artery disease include obesity , smoking , high cholesterol , high blood pressure , lack of exercise and diabetes . Cancer can affect
7384-412: The cell numbers of all the organs of the body and cell types . The skin of the body is also host to billions of commensal organisms as well as immune cells. Not all parts of the body are made from cells. Cells sit in an extracellular matrix that consists of proteins such as collagen , surrounded by extracellular fluids. Cells in the body function because of DNA . DNA sits within the nucleus of
7488-438: The center of Greek scholarship, this division of people and language is quite similar to the results of modern archaeological-linguistic investigation. One standard formulation for the dialects is: West vs. non-West Greek is the strongest-marked and earliest division, with non-West in subsets of Ionic-Attic (or Attic-Ionic) and Aeolic vs. Arcadocypriot, or Aeolic and Arcado-Cypriot vs. Ionic-Attic. Often non-West
7592-432: The covering of the body (the skin ), including hair and nails as well as other functionally important structures such as the sweat glands and sebaceous glands . The skin provides containment, structure, and protection for other organs, and serves as a major sensory interface with the outside world. The lymphatic system extracts, transports and metabolizes lymph, the fluid found in between cells. The lymphatic system
7696-539: The death rate from surgery by a substantial amount. The Physiological Society was founded in London in 1876 as a dining club. The American Physiological Society (APS) is a nonprofit organization that was founded in 1887. The Society is, "devoted to fostering education, scientific research, and dissemination of information in the physiological sciences." In 1891, Ivan Pavlov performed research on "conditional responses" that involved dogs' saliva production in response to
7800-615: The dialect of Sparta ), and Northern Peloponnesus Doric (including Corinthian ). All the groups were represented by colonies beyond Greece proper as well, and these colonies generally developed local characteristics, often under the influence of settlers or neighbors speaking different Greek dialects. After the conquests of Alexander the Great in the late 4th century BC, a new international dialect known as Koine or Common Greek developed, largely based on Attic Greek , but with influence from other dialects. This dialect slowly replaced most of
7904-517: The election of women was celebrated in 2015 with the publication of the book "Women Physiologists: Centenary Celebrations And Beyond For The Physiological Society." ( ISBN 978-0-9933410-0-7 ) Prominent women physiologists include: Human physiology Animal physiology Plant physiology Fungal physiology Protistan physiology Algal physiology Bacterial physiology Ancient Greek language Ancient Greek ( Ἑλληνῐκή , Hellēnikḗ ; [hellɛːnikɛ́ː] ) includes
8008-458: The form of proteins (which are broken down into amino acids ), fats , vitamins and minerals (the last of which are mainly ionic rather than molecular). After being swallowed , food moves through the gastrointestinal tract by means of peristalsis : the systematic expansion and contraction of muscles to push food from one area to the next. Digestion begins in the mouth , which chews food into smaller pieces for easier digestion. Then it
8112-673: The forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek ( c. 1400–1200 BC ), Dark Ages ( c. 1200–800 BC ), the Archaic or Epic period ( c. 800–500 BC ), and the Classical period ( c. 500–300 BC ). Ancient Greek was the language of Homer and of fifth-century Athenian historians, playwrights, and philosophers . It has contributed many words to English vocabulary and has been
8216-403: The heart , though it is exceedingly rare and has usually metastasized from another part of the body such as the lungs or breasts . This is because the heart cells quickly stop dividing and all growth occurs through size increase rather than cell division . The gallbladder is a hollow pear-shaped organ located posterior to the inferior middle part of the right lobe of the liver . It
8320-434: The heart. From here, it is pumped into the body's largest artery , the aorta , and then progressively smaller arteries and arterioles until it reaches tissue. Here, blood passes from small arteries into capillaries , then small veins and the process begins again. Blood carries oxygen , waste products, and hormones from one place in the body to another. Blood is filtered at the kidneys and liver . The body consists of
8424-561: The historical Dorians . The invasion is known to have displaced population to the later Attic-Ionic regions, who regarded themselves as descendants of the population displaced by or contending with the Dorians. The Greeks of this period believed there were three major divisions of all Greek people – Dorians, Aeolians, and Ionians (including Athenians), each with their own defining and distinctive dialects. Allowing for their oversight of Arcadian, an obscure mountain dialect, and Cypriot, far from
8528-476: The historical circumstances of the times imply that the overall groups already existed in some form. Scholars assume that major Ancient Greek period dialect groups developed not later than 1120 BC, at the time of the Dorian invasions —and that their first appearances as precise alphabetic writing began in the 8th century BC. The invasion would not be "Dorian" unless the invaders had some cultural relationship to
8632-500: The humoral theory of disease, which also consisted of four primary qualities in life: hot, cold, wet and dry. Galen ( c. 130 –200 AD) was the first to use experiments to probe the functions of the body. Unlike Hippocrates, Galen argued that humoral imbalances can be located in specific organs, including the entire body. His modification of this theory better equipped doctors to make more precise diagnoses. Galen also played off of Hippocrates' idea that emotions were also tied to
8736-457: The humors, and added the notion of temperaments: sanguine corresponds with blood; phlegmatic is tied to phlegm; yellow bile is connected to choleric; and black bile corresponds with melancholy. Galen also saw the human body consisting of three connected systems: the brain and nerves, which are responsible for thoughts and sensations; the heart and arteries, which give life; and the liver and veins, which can be attributed to nutrition and growth. Galen
8840-409: The individual." In more differentiated organisms, the functional labor could be apportioned between different instruments or systems (called by him as appareils ). In 1858, Joseph Lister studied the cause of blood coagulation and inflammation that resulted after previous injuries and surgical wounds. He later discovered and implemented antiseptics in the operating room, and as a result, decreased
8944-401: The leaves, and growth of shoots towards light are examples of plant physiology. Human physiology is the study of how the human body's systems and functions work together to maintain a stable internal environment. It includes the study of the nervous, endocrine, cardiovascular, respiratory, digestive, and urinary systems, as well as cellular and exercise physiology. Understanding human physiology
9048-449: The level of organs and systems within systems. The endocrine and nervous systems play major roles in the reception and transmission of signals that integrate function in animals. Homeostasis is a major aspect with regard to such interactions within plants as well as animals. The biological basis of the study of physiology, integration refers to the overlap of many functions of the systems of the human body, as well as its accompanied form. It
9152-421: The lungs, to column-like cells that line the stomach . Endothelial cells are cells that line internal cavities including blood vessels and glands. Lining cells regulate what can and cannot pass through them, protect internal structures, and function as sensory surfaces. Organs , structured collections of cells with a specific function, mostly sit within the body, with the exception of skin . Examples include
9256-415: The movement of the heart via pericardial fluid . The heart works by pumping blood around the body allowing oxygen , nutrients , waste , hormones and white blood cells to be transported. The heart is composed of two atria and two ventricles . The primary purpose of the atria is to allow uninterrupted venous blood flow to the heart during ventricular systole . This allows enough blood to get into
9360-407: The nervous system. The purpose of the reproductive system is to reproduce and nurture the growth of offspring. The functions include the production of germ cells and hormones. The sex organs of the male reproductive system and the female reproductive system develops and mature at puberty . These systems include the internal and external genitalia . Female puberty generally occurs between
9464-409: The notion of physiological division of labor, which allowed to "compare and study living things as if they were machines created by the industry of man." Inspired in the work of Adam Smith , Milne-Edwards wrote that the "body of all living beings, whether animal or plant, resembles a factory ... where the organs, comparable to workers, work incessantly to produce the phenomena that constitute the life of
9568-508: The older dialects, although the Doric dialect has survived in the Tsakonian language , which is spoken in the region of modern Sparta. Doric has also passed down its aorist terminations into most verbs of Demotic Greek . By about the 6th century AD, the Koine had slowly metamorphosed into Medieval Greek . Phrygian is an extinct Indo-European language of West and Central Anatolia , which
9672-487: The perfect stem eilēpha (not * lelēpha ) because it was originally slambanō , with perfect seslēpha , becoming eilēpha through compensatory lengthening. Reduplication is also visible in the present tense stems of certain verbs. These stems add a syllable consisting of the root's initial consonant followed by i . A nasal stop appears after the reduplication in some verbs. The earliest extant examples of ancient Greek writing ( c. 1450 BC ) are in
9776-602: The same year, Charles Bell finished work on what would later become known as the Bell–Magendie law , which compared functional differences between dorsal and ventral roots of the spinal cord . In 1824, François Magendie described the sensory roots and produced the first evidence of the cerebellum's role in equilibration to complete the Bell–Magendie law. In the 1820s, the French physiologist Henri Milne-Edwards introduced
9880-837: The subdisciplines of physiology: Although there are differences between animal , plant , and microbial cells, the basic physiological functions of cells can be divided into the processes of cell division , cell signaling , cell growth , and cell metabolism . Plant physiology is a subdiscipline of botany concerned with the functioning of plants. Closely related fields include plant morphology , plant ecology , phytochemistry , cell biology , genetics , biophysics , and molecular biology . Fundamental processes of plant physiology include photosynthesis , respiration , plant nutrition , tropisms , nastic movements , photoperiodism , photomorphogenesis , circadian rhythms , seed germination , dormancy , and stomata function and transpiration . Absorption of water by roots, production of food in
9984-517: The syllabic script Linear B . Beginning in the 8th century BC, however, the Greek alphabet became standard, albeit with some variation among dialects. Early texts are written in boustrophedon style, but left-to-right became standard during the classic period. Modern editions of ancient Greek texts are usually written with accents and breathing marks , interword spacing , modern punctuation , and sometimes mixed case , but these were all introduced later. The beginning of Homer 's Iliad exemplifies
10088-525: The systems and organs of the human body and their functions. Many systems and mechanisms interact in order to maintain homeostasis , with safe levels of substances such as sugar , iron , and oxygen in the blood. The body is studied by health professionals , physiologists, anatomists, and artists to assist them in their work. The human body is composed of elements including hydrogen , oxygen , carbon , calcium and phosphorus . These elements reside in trillions of cells and non-cellular components of
10192-405: The urinary tract and can cause pain when urinating, frequent urination and even death if left untreated. Renal failure occurs when the kidneys fail to adequately filter waste from the blood and can lead to death if not treated with dialysis or kidney transplantation . Cancer can affect the bladder , kidneys , urethra and ureters , with the latter two being far more rare. Human anatomy
10296-417: The ventricles during atrial systole . Consequently, the atria allows a cardiac output roughly 75% greater than would be possible without them. The purpose of the ventricles is to pump blood to the lungs through the right ventricle and to the rest of the body through the left ventricle. The heart has an electrical conduction system to control the contraction and relaxation of the muscles. It starts in
10400-401: The water inside and outside cells is carefully maintained. The main electrolytes in body water outside cells are sodium and chloride , whereas within cells it is potassium and other phosphates . The body contains trillions of cells , the fundamental unit of life. At maturity, there are roughly 30 trillion cells, and 38 trillion bacteria in the body, an estimate arrived at by totaling
10504-480: Was Aeolic. For example, fragments of the works of the poet Sappho from the island of Lesbos are in Aeolian. Most of the dialect sub-groups listed above had further subdivisions, generally equivalent to a city-state and its surrounding territory, or to an island. Doric notably had several intermediate divisions as well, into Island Doric (including Cretan Doric ), Southern Peloponnesus Doric (including Laconian ,
10608-399: Was also the founder of experimental physiology. And for the next 1,400 years, Galenic physiology was a powerful and influential tool in medicine . Jean Fernel (1497–1558), a French physician, introduced the term "physiology". Galen, Ibn al-Nafis , Michael Servetus , Realdo Colombo , Amato Lusitano and William Harvey , are credited as making important discoveries in the circulation of
10712-950: Was founded in 1887 and included only men in its ranks. In 1902, the American Physiological Society elected Ida Hyde as the first female member of the society. Hyde, a representative of the American Association of University Women and a global advocate for gender equality in education, attempted to promote gender equality in every aspect of science and medicine. Soon thereafter, in 1913, J.S. Haldane proposed that women be allowed to formally join The Physiological Society , which had been founded in 1876. On 3 July 1915, six women were officially admitted: Florence Buchanan , Winifred Cullis , Ruth Skelton , Sarah C. M. Sowton , Constance Leetham Terry , and Enid M. Tribe . The centenary of
10816-408: Was provided by animal experimentation . Due to the frequent connection between form and function, physiology and anatomy are intrinsically linked and are studied in tandem as part of a medical curriculum. Involving evolutionary physiology and environmental physiology , comparative physiology considers the diversity of functional characteristics across organisms. The study of human physiology as
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