Human body

From WikiProjectMed
Jump to navigation Jump to search

Female (left) and male (right) adult human bodies photographed in ventral (above) and dorsal (below) perspectives. Naturally-occurring pubic, body, and facial hair have been deliberately removed to show anatomy.

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. They ensure homeostasis and the viability of the human body.

It consists of head, hair, neck, torso (which includes the thorax and abdomen), arms and hands, legs and feet.

The study of the human body includes anatomy, physiology, histology and embryology. The body varies anatomically in known ways. Physiology focuses on 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 and oxygen in the blood.

The body is studied by health professionals, physiologists, anatomists, and artists to assist them in their work.

Composition

Elements of the human body by mass. Trace elements are less than 1% combined (and each less than 0.1%).
Element Symbol Percent mass Percent atoms
Oxygen O 65.0 24.0
Carbon C 18.5 12.0
Hydrogen H 9.5 62.0
Nitrogen N 3.2 1.1
Calcium Ca 1.5 0.22
Phosphorus P 1.0 0.22
Potassium K 0.4 0.03
Sulfur S 0.3 0.038
Sodium Na 0.2 0.037
Chlorine Cl 0.2 0.024
Magnesium Mg 0.1 0.015
Trace elements < 0.1 < 0.3

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 the body.

The adult male body is about 60% water for a total 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.[1] The content, acidity and composition of 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.[2]

Cells

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,[3][4] an estimate arrived at by totaling 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.[5] 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.

Genome

Cells in the body function because of DNA. DNA sits within the nucleus of a cell. Here, parts of DNA are copied and sent to the body of the cell via RNA.[6] 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.[7] However, not all cells have DNA; some cells such as mature red blood cells lose their nucleus as they mature.

Tissues

The body consists of many different types of tissue, defined as cells that act with a specialised function.[8] 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.[9]

Cells that lie on 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 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.[9]

Organs

Organs, structured collections of cells with a specific function,[10] mostly sit within the body, with the exception of skin. Examples include 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.

Heart

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 the movement of the heart via pericardial fluid.[11] The heart works by pumping blood around the body allowing oxygen, nutrients, waste, hormones and white blood cells to be transported.

Diagram of the human heart

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 the ventricles during atrial systole. Consequently, the atria allows a cardiac output roughly 75% greater than would be possible without them.[12] 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.[13]

The heart has an electrical conduction system to control the contraction and relaxation of the muscles. It starts in 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.[14]

Coronary artery disease is the leading cause of death worldwide, making up 16% of all deaths.[15] It is caused by 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,[16] a condition known as myocardial infarction or heart attack, this can cause heart failure or cardiac arrest and eventually death.[17] Risk factors for coronary artery disease include obesity, smoking, high cholesterol, high blood pressure, lack of exercise and diabetes.[18] Cancer can affect 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.[19]

Gallbladder

The gallbladder is a hollow pear-shaped organ located posterior to the inferior middle part of the right lobe of the liver. It 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.[20]

The gallbladder gets its blood supply from the cystic artery, which in most people, emerges from the right hepatic artery.[20]

Gallstones 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 and or center of the abdomen. Nausea and vomiting may also occur. Typical treatment is removal of the gallbladder through a procedure called a cholecystectomy.[21][22] Having gallstones is a risk factor for gallbladder cancer, which although quite uncommon, is rapidly fatal if not diagnosed early.[23]

Systems

  • Circulatory system

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 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 the spleen and bone marrow.[24][25][26]

  • Digestive system
Digestive system

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 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.[27][28]

Digestion begins in the mouth, which chews food into smaller pieces for easier digestion. Then it 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 the anus.[28]

  • Endocrine system

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.[29]

  • Immune system

The immune system consists of 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.[30]

Skin
  • Integumentary system

The integumentary system consists of 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.[31][32]

  • Lymphatic system

The lymphatic system extracts, transports and metabolizes lymph, the fluid found in between cells. The lymphatic system is similar to the circulatory system in terms of both its structure and its most basic function, to carry a body fluid.[33]

  • Musculoskeletal system

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 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.[34]

  • Nervous system
Nervous 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 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.[35]

From a structural perspective, the nervous system is typically subdivided into two component parts: 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.[36] It remains a matter of some debate whether the CNS directly gives rise to consciousness.[citation needed] The peripheral nervous system (PNS) is mostly responsible for gathering information with sensory neurons and directing body movements with motor neurons.[36]

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.[37]

The nervous system 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 the nervous system.[36]

  • Reproductive system
Male gonad (testes, left) and female gonad (ovaries, right)

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.[38] 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.

Internal gross anatomy of the female reproductive system

Female puberty generally occurs between 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.[39] Male puberty sees the further development of the penis and testes.[40]

The female inner sex organs are the two ovaries, their fallopian tubes, 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.[39][41] The female external sex organs include the vulva, labia, clitoris, and vaginal opening.[42][39]

The male external genitalia include the penis and scrotum that contains 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 epididymis, vas deferens, and some accessory glands.

Diseases that affect the reproductive system include polycystic ovary syndrome,[43] a number of disorders of the testicles including testicular torsion,[44][45] and a number of sexually transmitted infections including syphilis, HIV, chlamydia, HPV and genital warts. [46][47] Cancer can affect most parts of the reproductive system including the penis, testicles, prostate, ovaries, cervix, vagina, fallopian, uterus and vulva.[48]

  • Respiratory system

The respiratory system consists of the nose, nasopharynx, trachea, and lungs. It brings oxygen from 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 the air and into the bloodstream.[49][50]

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.[50] In asthma, the respiratory system is persistently inflamed, causing wheezing and/or shortness of breath. Pneumonia occurs through infection of the alveoli, and may be caused by tuberculosis. Emphysema, commonly a result of smoking, is caused by damage to connections between the alveoli.[51]

  • Urinary system
Female urinary system

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, 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.[52] 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.[53] The urine 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 the brain signals it to relax the urinary sphincter and release the urine into the urethra starting urination.[54] 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 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.[55] Cancer can affect the bladder, kidneys, urethra and ureters, with the latter two being far more rare.[56]

Anatomy

Cavities of human body

Human anatomy 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 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 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 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 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 is influenced by the distribution of bones, muscle and fat tissue.[57]

Physiology

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 the body in a stable state with safe levels of substances such as sugar and oxygen in the blood.[58]

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 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).[58]

Development

Baby being carried.

Development of the human body is the process of growth to maturity. The process begins with fertilisation, where an egg released from 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 the process of aging.

Society and culture

Professional study

Anatomical study by Leonardo da Vinci

Health professionals learn about the human body from illustrations, models, and demonstrations. Medical and dental students in addition gain practical experience, for example by dissection of cadavers. Human anatomy, physiology, and biochemistry are basic medical sciences, generally taught to medical students in their first year at medical school.[59][60][61]

Depiction

Figure drawing by Lovis Corinth (before 1925)

In Western societies, the contexts for depictions of the human body include information, art and pornography. Information includes both science and education, such as anatomical drawings. Any ambiguous image not easily fitting into one of these categories may be misinterpreted, leading to disputes.[62] The most contentious disputes are between fine art and erotic images, which define the legal distinction of which images are permitted or prohibited.

History of anatomy

Two facing pages of text with woodcuts of naked male and female figures, in the Epitome by Andreas Vesalius, 1543

In Ancient Greece, the Hippocratic Corpus described the anatomy of the skeleton and muscles.[63] The 2nd century physician Galen of Pergamum compiled classical knowledge of anatomy into a text that was used throughout the Middle Ages.[64] In the Renaissance, Andreas Vesalius (1514–1564) pioneered the modern study of human anatomy by dissection, writing the influential book De humani corporis fabrica.[65][66] Anatomy advanced further with the invention of the microscope and the study of the cellular structure of tissues and organs.[67] Modern anatomy uses techniques such as magnetic resonance imaging, computed tomography, fluoroscopy and ultrasound imaging to study the body in unprecedented detail.[68]

History of physiology

The study of human physiology began with Hippocrates in Ancient Greece, around 420 BCE, and with Aristotle (384–322 BCE) who applied critical thinking and emphasis on the relationship between structure and function. Galen (c. 126 – c. 199) was the first to use experiments to probe the body's functions.[69] The term physiology was introduced by the French physician Jean Fernel (1497–1558). In the 17th century, William Harvey (1578–1657) described the circulatory system, pioneering the combination of close observation with careful experiment.[70] In the 19th century, physiological knowledge began to accumulate at a rapid rate with the cell theory of Matthias Schleiden and Theodor Schwann in 1838, that organisms are made up of cells. Claude Bernard (1813–1878) created the concept of the milieu interieur (internal environment), which Walter Cannon (1871–1945) later said was regulated to a steady state in homeostasis. In the 20th century, the physiologists Knut Schmidt-Nielsen and George Bartholomew extended their studies to comparative physiology and ecophysiology.[71] Most recently, evolutionary physiology has become a distinct subdiscipline.[72]

See also

Human body lists

References

  1. ^ "Fluid Physiology". Anaesthesiamcq. Archived from the original on 3 May 2005. Retrieved 2 September 2016.
  2. ^ Ganong's 2016, p. 5.
  3. ^ Sender, Ron; Fuchs, Shai; Milo, Ron (2016). "Revised estimates for the number of human and bacteria cells in the body". PLOS Biology. 14 (8): e1002533. bioRxiv 10.1101/036103. doi:10.1371/journal.pbio.1002533. PMC 4991899. PMID 27541692.
  4. ^ Hatton, Ian A.; Galbraith, Eric D.; Merleau, Nono S. C.; Miettinen, Teemu P.; Smith, Benjamin McDonald; Shander, Jeffery A. (26 September 2023). "The human cell count and size distribution". Proceedings of the National Academy of Sciences. 120 (39): e2303077120. Bibcode:2023PNAS..12003077H. doi:10.1073/pnas.2303077120. ISSN 0027-8424. PMC 10523466. PMID 37722043.
  5. ^ Sfriso, R; Egert, M; Gempeler, M; Voegeli, R; Campiche, R (April 2020). "Revealing the secret life of skin - with the microbiome you never walk alone". International journal of cosmetic science. 42 (2): 116–126. doi:10.1111/ics.12594. PMC 7155096. PMID 31743445.
  6. ^ Ganong's 2016, p. 16.
  7. ^ "Gene Expression | Learn Science at Scitable". www.nature.com. Archived from the original on 31 October 2010. Retrieved 29 July 2017.
  8. ^ "tissue – definition of tissue in English". Oxford Dictionaries| English. Archived from the original on 5 October 2016. Retrieved 17 September 2016.
  9. ^ a b Gray's Anatomy 2008, p. 27.
  10. ^ "organ | Definition, meaning & more". www.collinsdictionary.com. Collins Dictionary. Retrieved 17 September 2016.
  11. ^ Jaworska-Wilczynska, Maria; Trzaskoma, Pawel; Szczepankiewicz, Andrzej A.; Hryniewiecki, Tomasz (2016). "Pericardium: structure and function in health and disease". Folia Histochemica et Cytobiologica. 54 (3): 121–125. doi:10.5603/FHC.a2016.0014. ISSN 1897-5631. PMID 27654013.
  12. ^ Anderson, Robert M. (1999). "Chapter 1: Normal Physiology". The Gross Physiology of the Cardiovascular System (2nd ed.). p. 11.
  13. ^ "Ventricle | heart". Encyclopedia Britannica. Retrieved 7 August 2021.
  14. ^ "How the Heart Works | NHLBI, NIH". www.nhlbi.nih.gov. Your Heart's Electrical System. Retrieved 7 August 2021.
  15. ^ "The top 10 causes of death". www.who.int. Retrieved 7 August 2021.
  16. ^ CDC (19 July 2021). "Coronary Artery Disease | cdc.gov". Centers for Disease Control and Prevention. Retrieved 7 August 2021.
  17. ^ CDC (11 January 2021). "Heart Attack Symptoms, Risk Factors, and Recovery | cdc.gov". Centers for Disease Control and Prevention. Retrieved 7 August 2021.
  18. ^ CDC (9 December 2019). "Know Your Risk for Heart Disease | cdc.gov". Centers for Disease Control and Prevention. Retrieved 7 August 2021.
  19. ^ "Matters of the Heart: Why Are Cardiac Tumors So Rare?". www.cancer.gov – National Cancer Institute. 10 February 2009. Retrieved 7 August 2021.
  20. ^ a b Nagral, Sanjay (2005). "Anatomy relevant to cholecystectomy". Journal of Minimal Access Surgery. 1 (2): 53–8. doi:10.4103/0972-9941.16527. PMC 3004105. PMID 21206646.
  21. ^ "Gallstones – Symptoms and causes". Mayo Clinic. Retrieved 7 August 2021.
  22. ^ "Gallstones – Diagnosis and treatment". www.mayoclinic.org. Retrieved 7 August 2021.
  23. ^ "Gallbladder cancer – Symptoms and causes". Mayo Clinic. Retrieved 7 August 2021.
  24. ^ "Cardiovascular System". U.S. National Cancer Institute. Archived from the original on 2 February 2007. Retrieved 16 September 2008.
  25. ^ Human Biology and Health. Upper Saddle River, NJ: Pearson Prentice Hall. 1993. ISBN 0-13-981176-1.
  26. ^ "The Cardiovascular System". State University of New York Downstate Medical Center. 8 March 2008. Archived from the original on 11 June 2016. Retrieved 16 September 2008.
  27. ^ "Your Digestive System and How It Works". National Institute of Health. Retrieved 4 September 2016.
  28. ^ a b "Your Digestive System & How it Works". National Institute of Diabetes and Digestive and Kidney Diseases. Retrieved 29 June 2019.
  29. ^ "Hormonal (endocrine) system". Victoria State Government. Retrieved 4 September 2016.
  30. ^ Zimmermann, Kim Ann. "Immune System: Diseases, Disorders & Function". LiveScience. Retrieved 4 September 2016.
  31. ^ Integumentary+System at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
  32. ^ Marieb, Elaine; Hoehn, Katja (2007). Human Anatomy & Physiology (7th ed.). Pearson Benjamin Cummings. p. 142. ISBN 978-0805359107.
  33. ^ Zimmermann, Kim Anne. "Lymphatic System: Facts, Functions & Diseases". LiveScience. Retrieved 4 September 2016.
  34. ^ Moore, Keith L.; Dalley, Arthur F.; Agur, Anne M. R. (2010). Moore's Clinically Oriented Anatomy. Phildadelphia: Lippincott Williams & Wilkins. pp. 2–3. ISBN 978-1-60547-652-0.
  35. ^ Lagassé, Paul (2001). "Nervous System". Columbia Encyclopedia (6th ed.). New York Detroit: Columbia University Press Sold and distributed by Gale Group. ISBN 978-0-7876-5015-5.
  36. ^ a b c Horton, James; Bradford, Alina; Zimmermann, Kim Ann (25 March 2022). "Nervous System: Facts, Function & Diseases". livescience.com. Retrieved 8 February 2023.
  37. ^ "Visual Guide to Your Nervous System". WebMD. Retrieved 8 February 2023.
  38. ^ "Introduction to the Reproductive System | SEER Training". training.seer.cancer.gov. Retrieved 5 March 2024.
  39. ^ a b c "Technical Issues In Reproductive Health". www.columbia.edu. Retrieved 7 August 2021.
  40. ^ "Accessory Glands | SEER Training". www.training.seer.cancer.gov. Retrieved 7 August 2021.
  41. ^ "Ovaries | SEER Training". www.training.seer.cancer.gov. Retrieved 7 August 2021.
  42. ^ "External Genitalia | SEER Training". www.training.seer.cancer.gov. Retrieved 7 August 2021.
  43. ^ Ndefo, Uche Anadu; Eaton, Angie; Green, Monica Robinson (June 2013). "Polycystic Ovary Syndrome". Pharmacy and Therapeutics. 38 (6): 336–355. ISSN 1052-1372. PMC 3737989. PMID 23946629.
  44. ^ Hyun, Grace S. (2018). "Testicular Torsion". Reviews in Urology. 20 (2): 104–106. doi:10.3909/riu0800 (inactive 17 January 2024). ISSN 1523-6161. PMC 6168322. PMID 30288149.{{cite journal}}: CS1 maint: DOI inactive as of January 2024 (link)
  45. ^ Ringdahl, Erika; Teague, Lynn (15 November 2006). "Testicular torsion". American Family Physician. 74 (10): 1739–1743. ISSN 0002-838X. PMID 17137004.
  46. ^ "Sexually Transmitted Diseases – Information from CDC". www.cdc.gov. 2 August 2021. Retrieved 7 August 2021.
  47. ^ "CDC – STDs – HPV". www.cdc.gov. 23 June 2021. Retrieved 7 August 2021.
  48. ^ "Reproductive Cancers | HHS Office of Population Affairs". opa.hhs.gov. Retrieved 7 August 2021.
  49. ^ Maton, Anthea; Hopkins, Jean; Johnson, Susan; McLaughlin, Charles William; Warner, Maryanna Quon; LaHart, David; Wright, Jill D. (2010). Human Biology and Health. Prentice Hall. pp. 108–118. ISBN 978-0-13-423435-9.
  50. ^ a b "Respiratory System". WebMD. Retrieved 8 February 2023.
  51. ^ Hoffman, Matthew. "Lung Diseases Overview". WebMD. Retrieved 8 February 2023.
  52. ^ "The Kidneys – a Basic Guide" (PDF). National Health Service. Archived (PDF) from the original on 9 January 2021. Retrieved 7 August 2021.
  53. ^ "Your Kidneys & How They Work | NIDDK". National Institute of Diabetes and Digestive and Kidney Diseases. Retrieved 7 August 2021.
  54. ^ "The Urinary Tract & How It Works | NIDDK". National Institute of Diabetes and Digestive and Kidney Diseases. Retrieved 7 August 2021.
  55. ^ Zimmermann, Kim Ann. "Urinary System: Facts, Functions & Diseases". LiveScience. Retrieved 4 September 2016.
  56. ^ Yaxley, Julian P. (2016). "Urinary tract cancers: An overview for general practice". Journal of Family Medicine and Primary Care. 5 (3): 533–538. doi:10.4103/2249-4863.197258. ISSN 2249-4863. PMC 5290755. PMID 28217578.
  57. ^ Gray, Henry (1918). "Anatomy of the Human Body". Bartleby. Retrieved 4 September 2016.
  58. ^ a b "What is Physiology?". Understanding Life. Archived from the original on 19 August 2017. Retrieved 4 September 2016.
  59. ^ "Introduction page, "Anatomy of the Human Body". Henry Gray". 1918. Retrieved 27 March 2007.
  60. ^ Drake, Richard Lee; Gray, Henry; Vogl, Wayne; Mitchell, Adam W. M. (2004). Publisher's page for Gray's Anatomy (39th ed.). ISBN 0-443-07168-3. Retrieved 27 March 2007.
  61. ^ Drake, Richard Lee; Gray, Henry; Vogl, Wayne; Mitchell, Adam W. M. (2004). Publisher's page for Gray's Anatomy (39th (US) ed.). ISBN 0-443-07168-3. Archived from the original on 9 February 2007. Retrieved 27 March 2007.
  62. ^ Eck, Beth A. (December 2001). "Nudity and Framing: Classifying Art, Pornography, Information, and Ambiguity". Sociological Forum. Springer. 16 (4): 603–632. doi:10.1023/A:1012862311849. JSTOR 684826. S2CID 143370129.
  63. ^ Gillispie, Charles Coulston (1972). Dictionary of Scientific Biography. Vol. VI. New York: Charles Scribner's Sons. pp. 419–427.
  64. ^ Nutton, Vivian (12 December 2023). "Galen of Pergamum". Encyclopædia Britannica 2006 Ultimate Reference Suite DVD.
  65. ^ "Vesalius's De Humanis Corporis Fabrica". Archive.nlm.nih.gov. Retrieved 29 August 2010.
  66. ^ "Andreas Vesalius (1514–1567)". Ingentaconnect. 1 May 1999. Archived from the original on 5 November 2011. Retrieved 29 August 2010.
  67. ^ "Microscopic anatomy". Encyclopædia Britannica. Retrieved 14 October 2013.
  68. ^ "Anatomical Imaging". McGraw Hill Higher Education. 1998. Archived from the original on 3 March 2016. Retrieved 25 June 2013.
  69. ^ Fell, C.; Griffith Pearson, F. (November 2007). "Thoracic Surgery Clinics: Historical Perspectives of Thoracic Anatomy". Thorac Surg Clin. 17 (4): 443–448, v. doi:10.1016/j.thorsurg.2006.12.001. PMID 18271159.
  70. ^ Zimmer, Carl (2004). "Soul Made Flesh: The Discovery of the Brain – and How It Changed the World". J Clin Invest. 114 (5): 604. doi:10.1172/JCI22882. PMC 514597.
  71. ^ Feder, Martin E. (1987). New directions in ecological physiology. New York: Cambridge University Press. ISBN 978-0-521-34938-3.
  72. ^ Garland, Theodore Jr.; Carter, P. A. (1994). "Evolutionary physiology" (PDF). Annual Review of Physiology. 56 (1): 579–621. doi:10.1146/annurev.ph.56.030194.003051. PMID 8010752. Archived from the original (PDF) on 12 April 2021. Retrieved 20 November 2013.

Books

External links