Circulatory system

Simplified diagram of the human Circulatory system in anterior view.

The circulatory system, also known as the cardiovascular system, blood-vascular system, or simply circulatory, is an essential system in the human body responsible for the transport of blood, nutrients, oxygen, and waste products. It comprises the heart, a robust muscular pump, and a network of vessels - arteries, veins, and capillaries. This closed circuit ensures that blood is continuously recirculated, maintaining homeostasis and facilitating cellular function.

Structure

• Heart: Serving as the central pumping mechanism, the heart ensures the movement of blood throughout the body.
• Arteries: These are robust, elastic vessels that transport blood away from the heart.
• Veins: Vessels responsible for carrying blood back to the heart.
• Capillaries: The tiniest of blood vessels, capillaries facilitate the exchange of nutrients, oxygen, and waste products between the blood and body tissues.

Development

The circulatory system is among the first to develop in a growing embryo, underlining its critical role. By the fourth week following fertilization, the primitive heart begins its rhythmic beating, well before many other major organ systems.

Functions

• Transport: At the core of its responsibilities, the circulatory system ensures the distribution of oxygen, nutrients, hormones, and other essential substances to cells and tissues.
• Waste Removal: The system aids in the removal of waste products, including carbon dioxide and metabolic byproducts, facilitating their excretion.
• Homeostasis Maintenance: By regulating the flow and distribution of blood, the circulatory system helps maintain a constant internal environment, ensuring cells receive necessary resources and waste products are efficiently removed.

Microscopic Functions

At the capillary level, blood achieves its ultimate purpose in transport. Through the thin walls of the capillaries, essential nutrients and oxygen are delivered to surrounding cellular fluids, while waste products are concurrently removed.

Regulation and Control

The circulatory system doesn't operate in isolation but is influenced by numerous control mechanisms that regulate and integrate its diverse functions. This coordination ensures specific body regions receive blood as per their requirements. Whether there's an increased demand for nutrients in a particular area or heightened waste production in another, these mechanisms maintain a stable environment around each cell.

Glossary of the circulatory system terms

• Accessory cephalic vein -  a vein that passes along the radial edge of the forearm and joins the cephalic vein near the elbow

• Adenitis -  inflammation of a gland or lymph node

• Adenoid -  relating to or resembling lymphatic glands or lymphoid tissue;  a collection of lymphatic tissue in the throat behind the uvula (on the posterior wall and roof of the nasopharynx)

• Adenosine -  (biochemistry) a nucleoside that is a structural component of nucleic acids; it is present in all living cells in a combined form as a constituent of DNA and RNA and ADP and ATP and AMP

• Amphetamine -  a central nervous system stimulant that increases energy and decreases appetite; used to treat narcolepsy and some forms of depression

• Anastomosis -  a natural or surgical joining of parts or branches of tubular structures so as to make or become continuous

• Aneurysm -  a cardiovascular disease characterized by a saclike widening of an artery resulting from weakening of the artery wall

• Angiogenesis -  the formation of new blood vessels

• Angiogenesis inhibitor -  a drug that is designed to prevent the growth of blood vessels that nourish tumors

• Angiography -  roentgenographic examination of blood vessels after injection of a radiopaque contrast medium; produces an angiogram

• Angiology -  the branch of medical science that studies the blood and lymph vessels and their disorders

• Angiopathy -  any disease of the blood vessels or lymph ducts

• Angioplasty -  an operation to repair a damaged blood vessel or unblock a coronary artery

• Angiotensin -  any of several vasoconstrictor substances (trade name Hypertensin) that cause narrowing of blood vessels

• Angiotensin -  any of several vasoconstrictor substances (trade name Hypertensin) that cause narrowing of blood vessels

• Angular artery -  the terminal branch of the facial artery

• Angular vein -  a short vein formed by the supraorbital vein and the supratrochlear vein and continuing as the facial vein

• Ankle -  a gliding joint between the distal ends of the tibia and fibula and the proximal end of the talus

• Anterior cardinal vein -  a major drainage channel from the cephalic part of the body

• Anterior jugular vein -  arises below the chin from veins draining the lower face; joins the external jugular vein

• Anti -  not in favor of (an action or proposal etc.);  a person who is opposed (to an action or policy or practice etc.)

• Aorta -  the large trunk artery that carries blood from the left ventricle of the heart to branch arteries

• Aortic orifice -  the orifice from the lower left chamber of the heart to the aorta

• Aortic valve -  a semilunar valve between the left ventricle and the aorta; prevents blood from flowing from the aorta back into the heart

• Aortitis -  inflammation of the aorta

• Appendicular artery -  the branch of the ileocolic artery that supplies the vermiform appendix

• Appendicular vein -  a vein that accompanies the appendicular artery and empties into the ileocolic vein

• Arteriole -  one of the small thin-walled arteries that end in capillaries

• Arteriolosclerosis -  sclerosis of the arterioles

• Arteriosclerosis -  sclerosis of the arterial walls

• Artery -  a major thoroughfare that bears important traffic; a blood vessel that carries blood from the heart to the body

• Artificial heart -  a pump that replaces the natural heart

• Atheroma -  a fatty deposit in the intima (inner lining) of an artery; can obstruct blood flow

• Atherosclerosis -  a stage of arteriosclerosis involving fatty deposits (atheromas) inside the arterial walls

• Atherosclerosis -  a stage of arteriosclerosis involving fatty deposits (atheromas) inside the arterial walls

• Atrioventricular node -  a node of specialized heart muscle located in the septal wall of the right atrium; receives impulses from the sinoatrial node and transmits them to atrioventricular bundle

• Atrium -  the central area in a building; open to the sky; any chamber that is connected to other chambers or passageways (especially one of the two upper chambers of the heart)

• Axillary vein -  a continuation of the basilic vein and brachial vein that becomes the subclavian vein

• B cell -  a lymphocyte derived from bone marrow that provides humoral immunity; it recognizes free antigen molecules in solution and matures into plasma cells that secrete immunoglobulin (antibodies) that inactivate the antigens

• Bangladesh -  a Muslim republic in southern Asia bordered by India to the north and west and east and the Bay of Bengal to the south; formerly part of India and then part of Pakistan; it achieved independence in 1971

• Banti's syndrome -  a disease characterized by congestion and enlargement of the spleen; accompanied by anemia or cirrhosis

• Basal vein -  a large vein passing along the medial surface of the temporal lobe and emptying into the great cerebral vein

• Basilic vein -  a vein that drains the back of the hand and forearm and empties into the axillary vein

• Blood -  temperament or disposition; the fluid (red in vertebrates) that is pumped by the heart; people viewed as members of a group; the descendants of one individual; a dissolute man in fashionable society;  smear with blood, as in a hunting initiation rite, where the face of a person is smeared with the blood of the kill

• Blood pressure -  the pressure of the circulating blood against the walls of the blood vessels; results from the systole of the left ventricle of the heart; sometimes measured for a quick evaluation of a person's health

• Blood vessel -  a vessel in which blood circulates

• Bone marrow -  the fatty network of connective tissue that fills the cavities of bones; very tender and very nutritious tissue from marrowbones

• Brachiocephalic vein -  veins formed by the union of the internal jugular and subclavian veins

• Bundle of His -  a bundle of modified heart muscle that transmits the cardiac impulse from the atrioventricular node to the ventricles causing them to contract

• Capillary -  long and slender with a very small internal diameter; of or relating to hair;  a tube of small internal diameter; holds liquid by capillary action; any of the minute blood vessels connecting arterioles with venules

• cardiac -  of or relating to the heart

• Cardiac cycle -  the complete cycle of events in the heart from the beginning of one heart beat to the beginning of the next; an electrical impulse conducted through the heart muscle that constricts the atria which is followed by constriction of the ventricles

• Cardiac muscle -  the muscle tissue of the heart; adapted to continued rhythmic contraction

• Cardiac output -  the amount of blood pumped out by the ventricles in a given period of time

• Cardiac pacemaker -  a specialized bit of heart tissue that controls the heartbeat

• Cardiac plexus -  a plexus of nerves supplying the heart and nearby structures

• Cardiac tamponade -  mechanical compression of the heart resulting from large amounts of fluid collecting in the pericardial space and limiting the heart's normal range of motion

• Cardiogenic shock -  shock caused by cardiac arrest

• Cardiology -  the branch of medicine dealing with the heart and its diseases

• Cardiology -  the branch of medicine dealing with the heart and its diseases

• Cardiovascular disease -  a disease of the heart or blood vessels

• Carditis -  inflammation of the heart

• Cardium -  type genus of the family Cardiidae: cockles

• Carotid body -  a chemoreceptor located near the bifurcations of the carotid arteries; monitors oxygen content of the blood and helps control respiration

• CD -  a digitally encoded recording on an optical disk that is smaller than a phonograph record; played back by a laser; a debt instrument issued by a bank; usually pays interest; the basic unit of luminous intensity adopted under the Systeme International d'Unites; equal to 1/60 of the luminous intensity per square centimeter of a black body radiating at the temperature of 2,046 degrees Kelvin; a soft bluish-white ductile malleable toxic bivalent metallic element; occurs in association with zinc ores

• cell -  (biology) the basic structural and functional unit of all organisms; they may exist as independent units of life (as in monads) or may form colonies or tissues as in higher plants and animals; a device that delivers an electric current as the result of a chemical reaction; a room where a prisoner is kept; small room is which a monk or nun lives; any small compartment; a small unit serving as part of or as the nucleus of a larger political movement; a hand-held mobile radiotelephone for use in an area divided into small sections, each with its own short-range transmitter/receiver

• Central veins of liver -  terminal branches of the hepatic veins that lie in the hepatic lobules and receive blood from the liver sinusoids

• Cephalic vein -  a large vein of the arm that empties into the axillary vein

• Cerebellar artery -  an artery that supplies the cerebellum

• character -  (genetics) an attribute (structural or functional) that is determined by a gene or group of genes; the inherent complex of attributes that determine a persons moral and ethical actions and reactions; an actor's portrayal of someone in a play; a formal recommendation by a former employer to a potential future employer describing the person's qualifications and dependability; a written symbol that is used to represent speech; a person of a specified kind (usually with many eccentricities); good repute; a characteristic property that defines the apparent individual nature of something; an imaginary person represented in a work of fiction (play or film or story);  engrave or inscribe characters on

• charity -  an activity or gift that benefits the public at large; a kindly and lenient attitude toward people; an institution set up to provide help to the needy; a foundation created to promote the public good (not for assistance to any particular individuals); pinnate-leaved European perennial having bright blue or white flowers

• Cherry -  of a color at the end of the color spectrum (next to orange); resembling the color of blood or cherries or tomatoes or rubies;  a red fruit with a single hard stone; any of numerous trees and shrubs producing a small fleshy round fruit with a single hard stone; many also produce a valuable hardwood; wood of any of various cherry trees especially the black cherry; a red the color of ripe cherries

• Churchill -  a Canadian town in northern Manitoba on Hudson Bay; important port for shipping grain; British statesman and leader during World War II; received Nobel prize for literature in 1953 (1874-1965); English general considered one of the greatest generals in history (1650-1722)

• Chyle -  a milky fluid consisting of lymph and emulsified fats; formed in the small intestine during digestion of ingested fats

• circulation -  the spread or transmission of something (as news or money) to a wider group or area; the dissemination of copies of periodicals (as newspapers or magazines); free movement or passage through a series of vessels (as of water through pipes or sap through a plant); movement through a circuit; especially the movement of blood through the heart and blood vessels; number of copies of a newspaper or magazine that are sold; (library science) the count of books that are loaned by a library over a specified period

• Circulation -  the spread or transmission of something (as news or money) to a wider group or area; the dissemination of copies of periodicals (as newspapers or magazines); free movement or passage through a series of vessels (as of water through pipes or sap through a plant); movement through a circuit; especially the movement of blood through the heart and blood vessels; number of copies of a newspaper or magazine that are sold; (library science) the count of books that are loaned by a library over a specified period

• Circulatory system -  the organs and tissues involved in circulating blood and lymph through the body

• Clone -  a group of genetically identical cells or organisms derived from a single cell or individual by some kind of asexual reproduction; an unauthorized copy or imitation; a person who is almost identical to another;  make multiple identical copies of

• Common facial vein -  vein formed by union of facial vein and the retromandibular vein and emptying into the jugular vein

• Common iliac artery -  terminal branches of the abdominal aorta

• Common iliac vein -  formed by the internal and external iliac veins; unites with its fellow from the opposite side of the body to form the inferior vena cava

• Complement -  something added to complete or make perfect; either of two parts that mutually complete each other; a word or phrase used to complete a grammatical construction; number needed to make up a whole force; a complete number or quantity; one of a series of enzymes in the blood serum that are part of the immune response;  make complete or perfect; supply what is wanting or form the complement to

• Compliance -  happy friendly agreement; the act of submitting; usually surrendering power to another; acting according to certain accepted standards; a disposition or tendency to yield to the will of others

• Copley -  American painter who did portraits of Paul Revere and John Hancock before fleeing to England to avoid the American Revolution (1738-1815)

• Coronary artery disease -  a stage of arteriosclerosis involving fatty deposits (atheromas) inside the arterial walls

• Coronary care unit -  a hospital unit specially staffed and equipped to treat patients with serious cardiac problems

• Coronary occlusion -  occlusion of a coronary artery caused either by progressive atherosclerosis or by a blood clot

• Coronary thrombosis -  obstruction of blood flow in a coronary artery by a blood clot (thrombus)

• Cystic vein -  vein that drains the gallbladder

• Cytopenia -  a deficiency of some cellular element of the blood

• Cytotoxic T cell -  T cell with CD8 receptor that recognizes antigens on the surface of a virus-infected cell and binds to the infected cell and kill it

• Deep cervical vein -  a vein that accompanies an artery of the same name

• Defibrillation -  treatment by stopping fibrillation of heart muscles (usually by electric shock delivered by a defibrillator)

• deficiency -  lack of an adequate quantity or number; the state of needing something that is absent or unavailable

• Descending aorta -  the descending part of the aorta that branches into the thoracic and abdominal aortae

• Diabetes -  any of several metabolic disorders marked by excessive urination and persistent thirst

• Diastasis -  separation of an epiphysis from the long bone to which it is normally attached without fracture of the bone

• Diastole -  the widening of the chambers of the heart between two contractions when the chambers fill with blood

• Dissection -  cutting so as to separate into pieces; detailed critical analysis or examination one part at a time (as of a literary work); a minute and critical analysis

• Dorsal scapular vein -  vein that is a tributary of the subclavian vein or external jugular vein and accompanies the descending scapular artery

• Ductus arteriosus -  a blood vessel in a fetus that bypasses pulmonary circulation by connecting the pulmonary artery directly to the ascending aorta; normally closes at birth

• Echocardiography -  a noninvasive diagnostic procedure that uses ultrasound to study to structure and motions of the heart

• Edema -  swelling from excessive accumulation of serous fluid in tissue

• Electrocardiography -  diagnostic procedure consisting of recording the activity of the heart electronically with a cardiograph (and producing a cardiogram)

• Embolectomy -  surgical removal of an embolus (usually from an artery)

• Endocardium -  the membrane that lines the cavities of the heart and forms part of the heart valves

• Endothelium -  an epithelium of mesoblastic origin; a thin layer of flattened cells that lines the inside of some body cavities

• Eosinopenia -  a decrease in the number of eosinophils in the blood

• Epstein -  British sculptor (born in the United States) noted for busts and large controversial works (1880-1959)

• Esophageal veins -  small veins from the esophagus emptying into the brachiocephalic vein or the azygos veins

• Experimental -  relying on observation or experiment; of the nature of or undergoing an experiment; relating to or based on experiment

• External iliac vein -  a continuation of the femoral vein; unites with the internal iliac vein to form the common iliac vein

• Exudate -  a substance that oozes out from plant pores;  release (a liquid) in drops or small quantities

• Fenestra -  a small opening covered with membrane (especially one in the bone between the middle and inner ear)

• Fetal circulation -  the system of blood vessels and structures through which blood moves in a fetus

• film -  a thin coating or layer; photographic material consisting of a base of celluloid covered with a photographic emulsion; used to make negatives or transparencies; a thin sheet of (usually plastic and usually transparent) material used to wrap or cover things; a medium that disseminates moving pictures; a form of entertainment that enacts a story by a sequence of images giving the illusion of continuous movement;  make a film or photograph of something; record in film

• Frank -  clearly manifest; evident; characterized by directness in manner or speech; without subtlety or evasion;  a smooth-textured sausage of minced beef or pork usually smoked; often served on a bread roll; a member of the ancient Germanic peoples who spread from the Rhine into the Roman Empire in the 4th century;  exempt by means of an official pass or letter, as from customs or other checks; stamp with a postmark to indicate date and time of mailing

• Gallop rhythm -  cardiac rhythm characterized by the presence of an extra sound; can indicate a heart abnormality

• Glucagon -  a hormone secreted by the pancreas; stimulates increases in blood sugar levels in the blood (thus opposing the action of insulin)

• Heart -  a playing card in the major suit that has one or more red hearts on it; an inclination or tendency of a certain kind; the courage to carry on; the hollow muscular organ located behind the sternum and between the lungs; its rhythmic contractions move the blood through the body; the locus of feelings and intuitions; a firm rather dry variety meat (usually beef or veal); a plane figure with rounded sides curving inward at the top and intersecting at the bottom; conventionally used on playing cards and valentines; the choicest or most essential or most vital part of some idea or experience; a positive feeling of liking; an area that is approximately central within some larger region

• Heart -  a playing card in the major suit that has one or more red hearts on it; an inclination or tendency of a certain kind; the courage to carry on; the hollow muscular organ located behind the sternum and between the lungs; its rhythmic contractions move the blood through the body; the locus of feelings and intuitions; a firm rather dry variety meat (usually beef or veal); a plane figure with rounded sides curving inward at the top and intersecting at the bottom; conventionally used on playing cards and valentines; the choicest or most essential or most vital part of some idea or experience; a positive feeling of liking; an area that is approximately central within some larger region

• Heart failure -  inability of the heart to pump enough blood to sustain normal bodily functions

• Heart rate -  the rate at which the heart beats; usually measured to obtain a quick evaluation of a person's health

• Heart Rhythm -  the rhythm of a beating heart

• Heart-to-Heart -  openly straightforward and direct without reserve or secretiveness;  an intimate talk in private

• Heart valve -  an implant that replaces a natural cardiac valve; a valve to control one-way flow of blood

• Hemodynamics -  the branch of physiology that studies the circulation of the blood and the forces involved

• HL -  a metric unit of volume or capacity equal to 100 liters

• hr -  a period of time equal to 1/24th of a day

• Hughes -  United States jurist who served as chief justice of the United States Supreme Court (1862-1948); United States industrialist who was an aviator and a film producer; during the last years of his life he was a total recluse (1905-1976); United States writer (1902-1967); English poet (born in 1930)

• Hydremia -  blood disorder in which there is excess fluid volume compared with the cell volume of the blood

• Hypertension -  a common disorder in which blood pressure remains abnormally high (a reading of 140/90 mm Hg or greater)

• Hypobetalipoproteinemia -  a hereditary disorder characterized by low levels of beta-lipoproteins and lipids and cholesterol

• Hypolipoproteinemia -  any of various disorders of lipoprotein and cholesterol metabolism that result in low levels of lipoprotein and cholesterol in the circulating blood

• Hypoproteinemia -  abnormally low level of protein in the blood; can indicate inadequate diet or intestinal or renal disorders

• Hypotension -  abnormally low blood pressure

• Ileocolic artery -  an artery that originates from the superior mesenteric artery and supplies the terminal part of the ileum and the cecum and the vermiform appendix and the ascending colon

• Ileocolic vein -  a vein that drains the end of the ileum and the appendix and the cecum and the lower part of the ascending colon

• Iliac artery -  one of the large arteries supplying blood to the pelvis and legs

• Iliac vein -  one of three veins draining the pelvic area

• Iliolumbar artery -  an artery that originates in the internal iliac artery and supplies the pelvic muscles and bones

• Iliolumbar vein -  a branch of the internal iliac vein

• immunology -  the branch of medical science that studies the body's immune system

• Inc -  a heterogeneous collection of groups united in their opposition to Saddam Hussein's government of Iraq; formed in 1992 it is comprised of Sunni and Shiite Arabs and Kurds who hope to build a new government

• Inferior epigastric vein -  empties into the external iliac vein

• Inferior labial artery -  a branch of the facial artery that supplies the lower lip

• Inferior ophthalmic vein -  a vein that drains a venous network in the floor and medial wall of the eye socket

• Infundibulum -  any of various funnel-shaped parts of the body (but especially the hypophyseal stalk)

• Intermittent claudication -  lameness due to pain in leg muscles because the blood supply is inadequate; pain subsides with rest

• Internal iliac vein -  a vein that unites with the external iliac vein to form the common iliac vein

• Ischemia -  local anemia in a given body part sometimes resulting from vasoconstriction or thrombosis or embolism

• James -  a river that rises in North Dakota and flows southward across South Dakota to the Missouri; a river in Virginia that flows east into Chesapeake Bay at Hampton Roads; (New Testament) disciple of Jesus; brother of John; author of the Epistle of James in the New Testament; writer who was born in the United States but lived in England (1843-1916); United States pragmatic philosopher and psychologist (1842-1910); United States outlaw who fought as a Confederate soldier and later led a band of outlaws that robbed trains and banks in the West until he was murdered by a member of his own gang (1847-1882); the first Stuart to be king of England and Ireland from 1603 to 1625 and king of Scotland from 1567 to 1625; he was the son of Mary Queen of Scots and he succeeded Elizabeth I; he alienated the British Parliament by claiming the divine right of kings (1566-1625); the last Stuart to be king of England and Ireland and Scotland; overthrown in 1688 (1633-1701); a Stuart king of Scotland who married a daughter of Henry VII; when England and France went to war in 1513 he invaded England and died in defeat at Flodden (1473-1513); a New Testament book attributed to Saint James the Apostle

• journal -  the part of the axle contained by a bearing; a record book as a physical object; a periodical dedicated to a particular subject; a daily written record of (usually personal) experiences and observations; a ledger in which transactions have been recorded as they occurred

• Kawasaki disease -  an acute disease of young children characterized by a rash and swollen lymph nodes and fever; of unknown cause

• Kinin -  any of a class of plant hormones that promote cell division and delay the senescence of leaves

• Labyrinthine artery -  a branch of the basilar artery that supplies the labyrinth

• Lacrimal artery -  an artery that originates from the ophthalmic artery and supplies the lacrimal gland and rectal eye muscles and the upper eyelid and the forehead

• Lacteal -  relating to or consisting of or producing or resembling milk;  any of the lymphatic vessels that convey chyle from the small intestine to the thoracic duct

• Left gastric vein -  arises from a union of veins from the gastric cardia; runs in the lesser omentum; empties into the portal vein

• Leukemia -  malignant neoplasm of blood-forming tissues; characterized by abnormal proliferation of leukocytes; one of the four major types of cancer

• Lipoprotein -  a conjugated protein having a lipid component; the principal means for transporting lipids in the blood

• Lung -  either of two saclike respiratory organs in the chest of vertebrates; serves to remove carbon dioxide and provide oxygen to the blood

• Lymph -  a thin coagulable fluid (similar to plasma but) containing white blood cells (lymphocytes) and chyle; is conveyed to the blood stream by lymphatic vessels

• Lymph node -  the source of lymph and lymphocytes

• Lymphangiectasia -  dilatation of a lymph vessel

• Lymphangioma -  benign angioma consisting of a mass of lymphatic vessels

• Lymphangitis -  inflammation of a lymph vessel

• Lymphatic system -  the interconnected system of spaces and vessels between body tissues and organs by which lymph circulates throughout the body

• Lymphatic vessel -  a vascular duct that carries lymph which is eventually added to the venous blood circulation

• Lymphedema -  swelling (usually in the legs) caused by lymph accumulating in the tissues

• Lymphocyte -  an agranulocytic leukocyte that normally makes up a quarter of the white blood cell count but increases in the presence of infection

• Lymphoma -  a neoplasm of lymph tissue that is usually malignant; one of the four major types of cancer

• Lymphopoiesis -  the formation of lymphocytes in the bone marrow and lymph nodes and thymus and spleen

• Macrophage -  a large phagocyte; some are fixed and other circulate in the blood stream

• Malaysia -  a constitutional monarchy in southeastern Asia on Borneo and the Malay Peninsula; achieved independence from the United Kingdom in 1957

• medical -  requiring or amenable to treatment by medicine especially as opposed to surgery; relating to the study or practice of medicine; of or belonging to Aesculapius or the healing art;  a thorough physical examination; includes a variety of tests depending on the age and sex and health of the person

• medication -  the act of treating with medicines or remedies; (medicine) something that treats or prevents or alleviates the symptoms of disease

• medicine -  the learned profession that is mastered by graduate training in a medical school and that is devoted to preventing or alleviating or curing diseases and injuries; (medicine) something that treats or prevents or alleviates the symptoms of disease; the branches of medical science that deal with nonsurgical techniques; punishment for one's actions;  treat medicinally, treat with medicine

• Miami -  a city and resort in southeastern Florida on Biscayne Bay; the best known city in Florida; a haven for retirees and a refuge for Cubans fleeing Castro; a member of the extinct Algonquian people formerly living in northern Indiana and southern Michigan

• Microcyte -  an abnormally small red blood cell (less than 5 microns in diameter)

• Middle thyroid vein -  a vein on each side that drains the lateral part of the thyroid and empties into the internal jugular vein

• Mitral valve -  valve with two cusps; situated between the left atrium and the left ventricle

• Myocarditis -  inflammation of the myocardium (the muscular tissue of the heart)

• Nasofrontal vein -  a vein located in the anterior medial part of the orbit; connects the superior ophthalmic with the angular vein

• NO -  quantifier; used with either mass s or plural count s for indicating a complete or almost complete lack or zero quantity of;  used to express refusal or denial or disagreement etc or especially to emphasize a negative statement; not in any degree or manner; not at all; referring to the degree to which a certain quality is present;  a negative; a radioactive transuranic element synthesized by bombarding curium with carbon ions; 7 isotopes are known

• nurse -  one skilled in caring for young children or the sick (usually under the supervision of a physician); a woman who is the custodian of children;  try to cure by special care of treatment, of an illness or injury; treat carefully; serve as a nurse; care for sick or handicapped people; give suck to; maintain (a theory, thoughts, or feelings)

• Nutrient artery -  an artery that supplies the medullary cavity of the long bone

• Oblique vein of the left atrium -  a tributary of the coronary sinus; on the posterior wall of the left atrium

• Obstructive shock -  shock caused by obstruction of blood flow

• Occipital vein -  a vein that drains the occipital region

• Omega -  the last (24th) letter of the Greek alphabet; the ending of a series or sequence

• Orthostatic hypotension -  low blood pressure occurring in some people when they stand up

• Ovarian vein -  one of the veins that drain the ovaries; the right opens into the inferior vena cava; the left opens into the left renal vein

• Paget -  English pathologist who discovered the cause of trichinosis (1814-1899)

• Palatine tonsil -  either of two masses of lymphatic tissue one on each side of the oral pharynx

• Pan -  chimpanzees; more closely related to Australopithecus than to other pongids; shallow container made of metal; cooking utensil consisting of a wide metal vessel; (Greek mythology) god of fields and woods and shepherds and flocks; represented as a man with goat's legs and horns and ears; identified with Roman Sylvanus or Faunus;  express a totally negative opinion of; wash dirt in a pan to separate out the precious minerals; make a sweeping movement

• Papillary muscle -  any of several muscles associated with the atrioventricular valves

• Paraumbilical vein -  small veins arising in skin around the navel; terminate as accessory portal veins

• Parve -  containing no meat or milk (or their derivatives) and thus eatable with both meat and dairy dishes according to the dietary laws of Judaism

• pathology -  the branch of medical science that studies the causes and nature and effects of diseases; any deviation from a healthy or normal condition

• Penumbra -  a fringe region of partial shadow around an umbra

• Perfusion -  pumping a liquid into an organ or tissue (especially by way of blood vessels)

• Perfusion -  pumping a liquid into an organ or tissue (especially by way of blood vessels)

• Pericardium -  a serous membrane with two layers that surrounds the heart

• Perineal artery -  a branch of the internal pudendal artery that supplies superficial structures of the perineum

• Peyer's patch -  any of several lymph nodes in the walls of the intestines near the junction of the ileum and colon

• Phlebitis -  inflammation of a vein (usually in the legs)

• Phlebothrombosis -  thrombosis of a vein without prior inflammation of the vein; associated with sluggish blood flow (as in prolonged bedrest or pregnancy or surgery) or with rapid coagulation of the blood

• Phlegmasia alba dolens -  painful thrombosis of the femoral vein in the leg following childbirth

• physiology -  processes and functions of an organism; the branch of the biological sciences dealing with the functioning of organisms

• Placenta -  the vascular structure in the uterus of most mammals providing oxygen and nutrients for and transferring wastes from the developing fetus; that part of the ovary of a flowering plant where the ovules form

• Plasma cell -  a cell that develops from a B lymphocyte in reaction to a specific antigen; found in bone marrow and sometimes in the blood

• Pneumonia -  respiratory disease characterized by inflammation of the lung parenchyma (excluding the bronchi) with congestion caused by viruses or bacteria or irritants

• Posterior cardinal vein -  a major drainage channel from the caudal part of the body

• Posterior labial veins -  veins that pass posterior from the labia majora to the internal pudendal vein

• Posterior meningeal artery -  branch of the ascending pharyngeal artery that supplies the dura mater of the posterior cranial fossa

• Posterior vein of the left ventricle -  arises near the apex of the heart and empties into the coronary sinus

• Pressure -  a force that compels; the somatic sensation that results from applying force to an area of skin; the force applied to a unit area of surface; measured in pascals (SI unit) or in dynes (cgs unit); an oppressive condition of physical or mental or social or economic distress; the act of pressing; the exertion of pressure; the state of demanding notice or attention;  to cause to do through pressure or necessity, by physical, moral or intellectual means :"She forced him to take a job in the city"; exert pressure on someone through threats

• professor -  someone who is a member of the faculty at a college or university

• Pterygoid plexus -  a plexus of veins draining the region of the pterygoid muscles and draining into the internal maxillary and anterior facial veins

• Pulmonary circulation -  circulation of blood between the heart and the lungs

• Pulmonary embolism -  blockage of the pulmonary artery by foreign matter or by a blood clot

• Pulmonary valve -  a semilunar valve between the right ventricle and the pulmonary artery; prevents blood from flowing from the artery back into the heart

• Pulp -  the soft inner part of a tooth; an inexpensive magazine printed on poor quality paper; any soft or soggy mass; a soft moist part of a fruit; a mixture of cellulose fibers;  reduce to pulp; remove the pulp from, as from a fruit

• Pulse -  the rhythmic contraction and expansion of the arteries with each beat of the heart; edible seeds of various pod-bearing plants (peas or beans or lentils etc.); the rate at which the heart beats; usually measured to obtain a quick evaluation of a person's health; (electronics) a sharp transient wave in the normal electrical state (or a series of such transients);  produce or modulate (as electromagnetic waves) in the form of short bursts or pulses or cause an apparatus to produce pulses; drive by or as if by pulsation; expand and contract rhythmically; beat rhythmically

• ratio -  the relative magnitudes of two quantities (usually expressed as a quotient)

• Refractory period -  (neurology) the time after a neuron fires or a muscle fiber contracts during which a stimulus will not evoke a response

• Regurgitation -  recall after rote memorization; backflow of blood through a defective heart valve; the reflex act of ejecting the contents of the stomach through the mouth

• Renin -  a proteolytic enzyme secreted by the kidneys; catalyzes the formation of angiotensin and thus affects blood pressure

• Resuscitation -  the act of reviving a person and returning them to consciousness

• Retromandibular vein -  posterior branch of the facial vein; formed by temporal veins in front of the ear

• Right gastric artery -  a branch of the hepatic artery that supplies the pyloric portion of the stomach on the lesser curvature

• Right gastric vein -  receives veins from the upper surfaces of the stomach and empties into the portal vein

• Sack -  the plundering of a place by an army or mob; usually involves destruction and slaughter; a bag made of paper or plastic for holding customer's purchases; a woman's full loose hiplength jacket; any of various light dry strong white wine from Spain and Canary Islands (including sherry); the quantity contained in a sack; the termination of someone's employment (leaving them free to depart); a loose-fitting dress hanging straight from the shoulders without a waist; a hanging bed of canvas or rope netting (usually suspended between two trees); swings easily; an enclosed space;  put in a sack; plunder (a town) after capture; make as a net profit; terminate the employment of

• Segal -  United States sculptor (born in 1924)

• Sinoatrial node -  a specialized bit of heart tissue that controls the heartbeat

• Size -  (used in combination) sized;  the property resulting from being one of a series of graduated measurements (as of clothing); the physical magnitude of something (how big it is); a large magnitude; the actual state of affairs; any glutinous material used to fill pores in surfaces or to stiffen fabrics;  make to a size; bring to a suitable size; sort according to size; cover or stiffen or glaze a porous material with size or sizing (a glutinous substance)

• Sphygmomanometer -  a pressure gauge for measuring blood pressure

• Spleen -  a large dark-red oval organ on the left side of the body between the stomach and the diaphragm; produces cells involved in immune responses; a feeling of resentful anger

• Spleen -  a large dark-red oval organ on the left side of the body between the stomach and the diaphragm; produces cells involved in immune responses; a feeling of resentful anger

• Splenectomy -  surgical removal of the spleen

• Stewart -  Scottish philosopher and follower of Thomas Reid (1753-1828); United States film actor who portrayed incorruptible but modest heros (1908-1997)

• Stroke -  a light touch with the hands; a single complete movement; (sports) the act of swinging or striking at a ball with a club or racket or bat or cue or hand; any one of the repeated movements of the limbs and body used for locomotion in swimming or rowing; a mark made by a writing implement (as in cursive writing); a light touch; the oarsman nearest the stern of the shell who sets the pace for the rest of the crew; a sudden loss of consciousness resulting when the rupture or occlusion of a blood vessel leads to oxygen lack in the brain; a punctuation mark (/) used to separate related items of information; the maximum movement available to a pivoted or reciprocating piece by a cam;  treat gingerly or carefully; strike a ball with a smooth blow; row at a particular rate; touch lightly and with affection, with brushing motions

• Subacute bacterial endocarditis -  a chronic bacterial infection of the endocardium and heart valves; symptoms develop slowly

• Sublingual vein -  a tributary of the lingual vein

• Superficial epigastric vein -  empties into the great saphenous vein

• Superior labial artery -  a branch of the facial artery that supplies the upper lip

• Superior ophthalmic vein -  a vein that begins at the inner angle of the eye socket and passes through the superior orbital fissure to empty into the cavernous sinus

• Superior thalamostriate vein -  a long vein that helps to form the internal cerebral vein

• Superior thyroid vein -  a vein on each side that drains the upper part of the thyroid and empties into the internal jugular vein

• Supraorbital vein -  drains the front of the scalp; unites with the supratrochlear vein to form the angular vein

• Systole -  the contraction of the chambers of the heart (especially the ventricles) to drive blood into the aorta and pulmonary artery

• T cell -  a small lymphocyte developed in the thymus; it orchestrates the immune system's response to infected or malignant cells

• Takayasu's arteritis -  disorder characterized by the absence of a pulse in both arms and in the carotid arteries

• Thoracic duct -  the major duct of the lymphatic system

• Thoracoepigastric vein -  a vein arising from the region of the superficial epigastric vein and opening into the axillary vein or thoracic vein

• Thrombectomy -  surgical removal of a blood clot (thrombus) from a blood vessel

• Thrombocytopenic purpura -  purpura associated with a reduction in circulating blood platelets which can result from a variety of factors

• Thrombolysis -  the process of breaking up and dissolving blood clots

• Thrombophlebitis -  phlebitis in conjunction with the formation of a blood clot (thrombus)

• Thrombosis -  the formation or presence of a thrombus (a clot of coagulated blood attached at the site of its formation) in a blood vessel

• Thrombus -  a blood clot formed within a blood vessel and remaining attached to its place of origin

• Thymus -  large genus of Old World mints: thyme; a ductless glandular organ at the base of the neck that produces lymphocytes and aids in producing immunity; atrophies with age

• Till -  unstratified soil deposited by a glacier; consists of sand and clay and gravel and boulders mixed together; a strongbox for holding cash; a treasury for government funds;  work land as by ploughing, harrowing, and manuring, in order to make it ready for cultivation

• Title -  an established or recognized right; an identifying appellation signifying status or function: e.g. `Mr.' or `General'; an appellation signifying nobility; the name of a work of art or literary composition etc.; a heading that names a statute or legislative bill; may give a brief summary of the matters it deals with; (usually plural) written material introduced into a movie or TV show to give credits or represent dialogue or explain an action; a general or descriptive heading for a section of a written work; an informal right to something; a legal document signed and sealed and delivered to effect a transfer of property and to show the legal right to possess it; the status of being a champion;  designate by an identifying term; give a title to

• Tonsil -  either of two masses of lymphatic tissue one on each side of the oral pharynx

• Tonsillectomy -  surgical removal of the palatine tonsils; commonly performed along with adenoidectomy

• Transudate -  a substance that transudes

• Tricuspid valve -  valve with three cusps; situated between the right atrium and the right ventricle; allows blood to pass from atrium to ventricle and closes to prevent backflow when the ventricle contracts

• Type -  a small metal block bearing a raised character on one end; produces a printed character when inked and pressed on paper; a subdivision of a particular kind of thing; all of the tokens of the same symbol; printed characters; (biology) the taxonomic group whose characteristics are used to define the next higher taxon; a person of a specified kind (usually with many eccentricities);  identify as belonging to a certain type; write by means of a keyboard with types

• UK -  a monarchy in northwestern Europe occupying most of the British Isles; divided into England and Scotland and Wales and Northern Ireland

• Umbilical vein -  a vein in the umbilical cord; returns nutrient blood from the placenta to the fetus

• Urea -  the chief solid component of mammalian urine; synthesized from ammonia and carbon dioxide and used as fertilizer and in animal feed and in plastics

• Varicocele -  dilatation of the veins associated with the spermatic cord in the testes

• Vasa vasorum -  any small blood vessel ramifying on the outside of a major artery or vein

• Vascularity -  the property being vascular

• Vasoconstriction -  decrease in the diameter of blood vessels

• Vasodilation -  dilation of blood vessels (especially the arteries)

• Vegetation -  inactivity that is passive and monotonous, comparable to the inactivity of plant life; an abnormal growth or excrescence (especially a warty excrescence on the valves of the heart); all the plant life in a particular region or period; the process of growth in plants

• Vein -  one of the horny ribs that stiffen and support the wing of an insect; a blood vessel that carries blood from the capillaries toward the heart; a distinctive style or manner; a layer of ore between layers of rock; any of the vascular bundles or ribs that form the branching framework of conducting and supporting tissues in a leaf or other plant organ;  make a veinlike pattern

• venous -  of or contained in or performing the function of the veins

• Ventricle -  a chamber of the heart that receives blood from an atrium and pumps it to the arteries; one of four connected cavities in the brain; is continuous with the central canal of the spinal cord and contains cerebrospinal fluid

• Ventricular aneurysm -  a localized dilation or protrusion on the wall of the left ventricle of the heart (occurring after a myocardial infarction)

• Venule -  a minute vein continuous with a capillary

• Vertebral vein -  a vein that goes through the foramina of the cervical vertebrae and forms a plexus around the vertebral artery; empties into the brachiocephalic vein

• Vitelline circulation -  circulation of blood between the embryo and the yolk sa

• Yolk sac -  membranous structure enclosing the yolk of eggs in birds reptiles marsupials and some fishes; circulates nutrients to the developing embryo; membranous structure that functions as the circulatory system in mammal embryos until the heart becomes functional

See Also

• Heart
• Artery
• Vein
• Capillary
• Homeostasis

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