Site MapHelpFeedbackGlossary Terms (M - R)
Glossary Terms (M - R)
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macula densa (23.0K)  An area of the distal convoluted tubule that touches afferent and efferent arterioles.
macular degeneration (40.0K)  A progressive disease that usually affects people over the age of 50. It occurs when the retina no longer receives an adequate blood supply.
magnetic resonance imaging (40.0K)  A viewing technique that uses a powerful magnetic field to produce an image of internal body structures.
major histocompatibility complex MHC (98.0K)  A large proteincomplex that plays a role in T cell activation.
malignant (20.0K)  A type of tumor or neoplasm that is invasive and destructive and that tends to metastasize; it is commonly known as cancerous.
maltase (28.0K)  An enzyme that digests sugars.
mammary glands (28.0K)  Accessory organs of the female reproductive system that secrete milk after pregnancy.
mammography (24.0K)  X-rayexamination of the breasts.
mandible (14.0K)  A bone that forms the lower portion of the jaw.
manipulation (18.0K)  The systematic movement of a patient’s body parts.
marrow (30.0K)  A substance that is contained in the medullary cavity. In adults, it consists primarily of fat.
mastoid process (28.0K)  A large bump on each temporal bone just behind each ear. It resembles a nipple, hence the name mastoid.
Material Safety Data Sheet MSDS (72.0K)  A form that is required for all hazardous chemicals or other substances used in the laboratory and that contains information about the product’s name, ingredients, chemical characteristics, physical and health hazards, guidelines for safe handling, and procedures to be followed in the event of exposure.
matrix (19.0K)  The basic format of an appointment book, established by blocking off times on the schedule during which the doctor is able to see patients. The material between the cells of connectivetissue.
matter (23.0K)  Anything that takes up space and has weight. Liquids, solids, and gases are matter.
maturation phase (32.0K)  The third phase of wound healing, in which scar tissue forms.
maxillae (25.0K)  A bone that forms the upper portion of the jaw.
Mayo stand (28.0K)  A movable stainless steel instrument tray on a stand.
medical asepsis (36.0K)  Measures taken to reduce the number of microorganisms, such as hand washing and wearing examination gloves, that do not necessarily eliminate microorganisms; also called clean technique.
medical practice act (39.0K)  A law that defines the exact duties that physicians and other healthcare personnel may perform.
medullary cavity (22.0K)  The canal that runs through the center of the diaphysis.
megakaryocyte (27.0K)  Cells within red blood marrow that give rise to platelets.
meiosis (23.0K)  A type of cell division in which each new cell contains only one member of each chromosome pair.
melanin (18.0K)  A pigment that is deposited throughout the layers of the epidermis.
melanocyte (33.0K)  A cell type within the epidermis that makes the pigment melanin.
melatonin (19.0K)  A hormone that helps to regulate circadian rhythms.
membrane potential (32.0K)  The potential inside a cell relative to the fluid outside the cell.
meninges (34.0K)  Membranes that protect the brain and spinal cord.
meningitis (22.0K)  An inflammation of the meninges.
meniscus (16.0K)  The curve in the air-to-liquid surface of a liquid specimen in a container.
menopause (28.0K)  The termination of the menstrual cycle due to the normal aging of the ovaries.
menses (18.0K)  The clinical term for menstrual flow.
menstral cycle (30.0K)  The female reproductive cycle. It consists of regular changes in the uterine lining that lead to monthly bleeding.
mensuration (26.0K)  The process of measuring.
mesoderm (22.0K)  The primary germ layer that gives rise to connective tissue and some epithelial tissue.
metabolism (29.0K)  The overall chemical functioning of the body, including all body processes that build small molecules into large ones (anabolism) and break down large molecules into small ones (catabolism).
metastasis (27.0K)  The transfer of abnormal cells to body sites far removed from the original tumor.
metatarsal (17.0K)  The bones that form the front of the foot.
microbiology (27.0K)  The study of microorganisms.
micropipette (23.0K)  A small pipette that holds a small, precise volume of fluid; used to collect capillary blood.
microvilli (20.0K)  Structures found in the lining of the small intestine. They greatly increase the surface area of the small intestine so it can absorb many nutrients.
micturition (28.0K)  The process of urination.
mineral (25.0K)  Natural,inorganic substances the body needs to help build and maintain body tissues and carry on life functions.
mirroring (14.0K)  Restating in your own words what a person is saying.
mitosis (20.0K)  A type of cell division that produces ordinary body, or somatic, cells; each new cell receives a complete set of paired chromosomes.
mitral valve (39.0K)  See bicuspid valve.
mobility aid (30.0K)  Devices that improve one’s ability to move from one place to another; also called mobility assistive devices.
modem (24.0K)  A device used to transfer information from one computer to another through telephone lines.
modified-block letter style (46.0K)  A letter format similar to full-block style, except that the dateline, complimentary closing, signature block, and notations are aligned and begin at the center of the page or slightly to the right of center.
molars (24.0K)  Back teeth that are flat and are designed to grind food.
mold (18.0K)  Fungi that grow into large, fuzzy, multicelled organisms that produce spores.
molecule (32.0K)  The smallest unit into which an element can be divided and still retain its properties; it is formed when atoms bond together.
monocytes (21.0K)  A large white blood cell with an oval or horseshoe-shaped nucleus that defends the body by phagocytosis; develops into a macrophage when it moves from blood into other tissues.
monosaccharide (28.0K)  A type of carbohydrate that is a simple sugar.
mordant (22.0K)  A substance, such as iodine, that can intensify or deepen the response a specimen has to a stain.
morphology (26.0K)  The study of the shape or form of objects.
morula (21.0K)  A zygote that has undergone cleavage and results in a ball of cells.
motherboard (40.0K)  The main circuit board of a computer that controls the other components in the system.
motor (28.0K)  Efferent neurons that carry information from the central nervous system to the effectors.
mucocutaneous exposure (38.0K)  Exposure to a pathogen through mucous membranes.
mucosa (24.0K)  The innermost layer of the wall of the alimentary canal.
mucous cells (23.0K)  Cells that are found in the salivary glands and the lining of the stomach and that secrete mucous.
MUGA scan (48.0K)  A radiologic procedure that evaluates the condition of the heart’s myocardium; it involves injection of radioisotopes that concentrate in the myocardium, followed by the use of a gamma camera to measure ventricular contractions to evaluate the patient’s heart wall.
multimedia (26.0K)  More than one medium, such as in graphics, sound, and text used to convey information.
multitasking (46.0K)  Running two or more computer software programs simultaneously.
multi-unit smooth muscle (48.0K)  A type of smooth muscle that is found in the iris of the eye and in the walls of blood vessels.
murmur (26.0K)  An abnormal heart sound heard when the ventricles contract and blood leaks back into the atria.
muscle (15.0K)  tissue type that is specialized to shorted and elongate.
muscle fatigue (27.0K)  A condition caused by a buildup of lactic acid.
muscle fiber (29.0K)  Muscle cells that are called fibers because of their long lengths.
muscular dystrophy (29.0K)  A group of inherited disorders characterized by a loss of muscle tissue and by muscle weakness.
mutation (27.0K)  An error that sometimes occurs when DNA is duplicated. When it occurs, it is passed to descendent cells and may or may not affect them in harmful Aways.
myasthenia gravis (45.0K)  An autoimmune disorder that is characterized by muscle weakness.
myelin (15.0K)  A fatty substance that insulates the axon and allows it to send nerve impulses quickly.
myelography (22.0K)  An x-ray visualization of the spinal cord after the injection of a radioactive contrast medium or air into the spinal subarachnoid space (between the second and innermost of three membranes that cover the spinal cord). This test can reveal tumors, cysts, spinal stenosis, or herniated disks.
myocardial infarction (36.0K)  A heart attack that occurs when the blood flow to the heart is reduced as a result of blockage in the coronary arteries or their branches.
myocardium (36.0K)  The middle and thickest layer of the heart. It is made primarily of cardiac muscle.
myofibrils (29.0K)  Long structures that fill the sarcoplasm of a muscle fiber.
myoglobin (31.0K)  A pigment contained in muscle cells that stores extra oxygen.
myometrium (21.0K)  The middle, thick muscular layer of the uterus.
myopia (16.0K)  A condition that occurs when light entering the eye is focused in front of the retina; commonly called nearsightedness.
myxedema (34.0K)  A severe type of hypothyroidism that is most common in women over the age of 50.
nail bed (19.0K)  The layer beneath each nail.
narcotic (20.0K)  A popular term for an opioid and term of choice in government agencies; see opioid.
nasal (22.0K)  Relating to the nose. The nasal bones fuse to form the bridge of the nose.
nasal conchae (28.0K)  Structures that extend from the lateral walls of the nasal cavity.
nasal mucosa (33.0K)  The lining of the nose.
nasal septum (21.0K)  A structure that divides the nasal cavity into a left and right portion.
nasolacrimal duct (42.0K)  A structure located on the medial aspect of each eyeball. These ducts drain tears into the nose.
nasopharynx (31.0K)  The portion of the pharynx behind the nasal cavity.
natural killer NK cells (69.0K)  Non-B and non-T lymphocytes. NK cells kill cancer cellsand virus-infected cells without previous exposure to the antigen.
needle biopsy (29.0K)  A procedure in which a needle and syringe are used to aspirate (withdraw by suction) fluid or tissue cells.
neonatal period (31.0K)  The first four weeks of the postnatal period of an offspring.
neonate (14.0K)  An infant during the first four weeks of life.
nephrons (20.0K)  Microscopic structures in the kidneys that filter blood and form urine.
nerve fiber (39.0K)  A structure that extends from the cell body. It consists of two types: axons and dendrites.
nerve impulse (25.0K)  Electrochemical messages transmitted from neurons to other neurons and effectors.
nervous (16.0K)  A tissue type located in the brain, spinal cord, and peripheral nerves.
network (21.0K)  A system that links several computers together.
networking (21.0K)  Making contacts with relatives, friends, and acquaintances that may have information about how to find a job in your field.
neuralgia (37.0K)  A medical condition characterized by severe pain along the distribution of a nerve.
neuroglial cell (24.0K)  Non-neuronal type of nervous tissue that is smaller and more abundant than neurons. Neuroglial cells support neurons.
neuron (32.0K)  A nerve cell; it carries nerve impulses between the brain or spinal cord and other parts of the body.
neurotransmitter (22.0K)  A chemical within the vesicles of the synaptic knob that is released into the postsynaptic structures when a nerve impulse reaches the synaptic knob.
neutrophils (23.0K)  A type of granular leukocyte that aids in phagocytosis by attacking bacterial invaders; also responsible for the release of pyrogens.
nocturia (17.0K)  Excessive nighttime urination.
noncompliant (39.0K)  The term used to describe a patient who does not follow the medical advice given.
noninvasive (23.0K)  Referring to procedures that do not require inserting devices, breaking the skin, or monitoring to the degree needed with invasive procedures.
nonsteroidal hormone (29.0K)  A type of hormone made of amino acids and proteins.
norepinephrine (22.0K)  A neurotransmitter released by sympathetic neurons onto organs and glands for fight-or-flight (stressful) situations.
nosocomial infection (43.0K)  An infection contracted in a hospital.
nuclear medicine (30.0K)  The use of radionuclides, or radioisotopes(radioactive elements or their compounds), to evaluate the bone,brain, lungs, kidneys, liver, pancreas,thyroid, and spleen; also known as radionuclide imaging.
nucleases (22.0K)  Pancreatic enzymes that digest nucleic acids.
nucleus (28.0K)  The control center of a cell; contains the chromosomes that direct cellularprocesses.
O and P specimen (38.0K)  An ova and parasites specimen, or a stool sample, that is examined for the presence of certain forms of protozoans or parasites, including their eggs (ova).
objective (21.0K)  Pertaining to data that is readily apparent and measurable, such as vital signs, test results, or physical examination findings.
occipital (18.0K)  Relating to the back of the head. The occipital bone forms the back of the skull.
occult blood (20.0K)  Blood contained in some other substance, not visible to the naked eye.
ocular (20.0K)  An eyepiece of a microscope.
oil-immersion objective (34.0K)  A microscope objective that is designed to be lowered into a drop of immersion oil placed directly above the prepared specimen under examination, eliminating the air space between the microscope slide and the objective and producing a much sharper, brighter image.
ointment (20.0K)  A form of topical drug; also known as a salve.
olfactory (17.0K)  Relating to the sense of smell.
oliguria (22.0K)  Insufficient production (or volume) of urine.
onychectomy (25.0K)  The removal of a fingernail or toenail.
oocyte (26.0K)  The immature egg.
oogenesis (24.0K)  The process of egg cell formation.
ophthalmoscope (27.0K)  A hand-held instrument with a light; used to view inner eye structures.
opioid (21.0K)  A natural or synthetic drug that produces opium-like effects.
optic chiasm (24.0K)  A structure located at the base of the brain where parts of the optic nerves cross. It carries visual information to the brain.
optical microscope (34.0K)  A microscope that uses light, concentrated through a condenser and focused through the object being examined, to project an image.
orbicularis oculi (38.0K)  The muscle in the eyelid responsible for blinking.
orbicularis oris (43.0K)  The muscle that opens and closes the mouth.
orbit (19.0K)  The eye socket, which forms a protective shell around the eye.
organ (31.0K)  Structure formed by the organization of two or more different tissue types that carries out specific functions.
organ systems (24.0K)  A system that consists of organs that join together to carry out vital functions.
organelle (19.0K)  A structure within a cell that performs a specific function.
organic (19.0K)  Pertaining to matter that contains carbon and hydrogen.
organism (24.0K)  A whole living being that is formed from organ systems.
origin (28.0K)  An attachment site of a skeletal muscle that does not move when a muscle contracts.
oropharynx (22.0K)  The portion of the pharynx behind the oral cavity.
osmosis (26.0K)  The diffusion of water across a semipermeable membrane such as a cell membrane.
ossification (34.0K)  The process of bone growth.
osteoblast (21.0K)  Boneforming cells that turn membrane into bone. They use excess blood calcium to build new bone.
osteoclast (37.0K)  Bonedissolving cells. When bone is dissolved, calcium is released into the bloodstream.
osteocyte (20.0K)  A cell of osseous tissue; also called a bone cell.
osteon (34.0K)  Elongated cylinders that run up and down the long axis of bone.
osteoporosis (24.0K)  An endocrine and metabolic disorder of the musculoskeletal system, more common in women than in men, characterized by hunched-over posture.
osteosarcoma (44.0K)  A type of bone cancer that originates from osteoblasts, the cells that make bony tissue.
oval window (29.0K)  The beginning of the inner ear.
ovulation (26.0K)  The process by which the ovaries release one ovum (egg) approximately every 28 days.
oxygen debt (21.0K)  A condition that develops when skeletal muscles are used strenuously for a minute or two.
oxyhemoglobin (22.0K)  Hemoglobin that is bound to oxygen. It is bright red in color.
oxytocin (27.0K)  A hormone that causes contraction of the uterus during childbirth and the ejection of milk from mammary glands during breast-feeding.
packed red blood cells (29.0K)  Red blood cells that collect at the bottom of a centrifuged blood sample.
palate (18.0K)  The roof of the mouth.
palatine (20.0K)  Bones that form the anterior potion of the roof of the mouth and the palate.
palatine tonsils (26.0K)  Two masses of lymphatic tissue located at the back of the throat.
palpation (15.0K)  A type of touch used by health-care providers to determine characteristics such as texture, temperature, shape, and the presence of movement.
palpitations (26.0K)  Unusually rapid, strong, or irregular pulsations of the heart.
pancreatic amylase (37.0K)  An enzyme that digests carbohydrates.
pancreatic lipase (29.0K)  An enzyme that digests lipids.
papillae (12.0K)  The “bumps” of the tongue in which the taste buds are found.
paranasal sinuses (30.0K)  Air-filled spaces within skull bones that open into the nasal cavity.
parasite (23.0K)  An organism that lives on or in another organism and relies on it for nourishment or some other advantage to the detriment of the host organism.
parasympathetic (21.0K)  A division of the autonomic nervous system that prepares the body for rest and digestion.
parathyroid hormone (34.0K)  A hormone that helps regulate calcium levels in the bloodstream.
parenteral nutrition (29.0K)  Nutrition obtained when specially prepared nutrients are injected directly into patients’ veins rather than taken by mouth.
paresthesias (42.0K)  Abnormal sensations ranging from burning to tingling.
parietal (32.0K)  Bones that form most of the top and sides of the skull.
parietal cells (30.0K)  Stomach cells that secrete hydrochloric acid, which is necessary to convert pepsinogen to pepsin Parietal cells also secrete intrinsic factor,which is necessary for vitamin B12 absorption.
parietal pericardium (43.0K)  The layer on top of the visceral pericardium.
parotid glands (26.0K)  The largest of the salivary glands. The parotid glands are located beneath the skin just in front of the ears.
patch test (18.0K)  An allergy test in which a gauze patch soaked with a suspected allergen is taped onto the skin with nonallergenic tape; used to discover the cause of contact dermatitis.
patella (16.0K)  The bone commonly referred to as the kneecap.
pathogens (31.0K)  A microorganism capable of causing disease.
patient compliance (25.0K)  Obedience in terms of following a physician’s orders.
patient record or chart (32.0K)  A compilation of important information about a patient’s medical history and present condition.
pectoral girdle (39.0K)  The structure that attaches the arms to the axial skeleton.
pelvic girdle (20.0K)  The structure that attaches the legs to the axial skeleton.
pepsin (20.0K)  An enzyme that allows the body to digest proteins.
pepsinogen (20.0K)  Substance that is secreted by the chief cells in the lining of the stomach and becomes pepsin in the presence of acid.
peptidases (26.0K)  Enzymes that digest proteins.
percussion (21.0K)  Tapping or striking the body to hear sounds or feel vibration.
percutaneous exposure (45.0K)  Exposure to a pathogen through a puncture wound or needlestick.
pericardium (19.0K)  A membrane that covers the heart and large blood vessels attached to it.
perilymph (23.0K)  A fluid in the inner ear. When this fluid moves, it activates hearing and equilibrium receptors.
perimetrium (24.0K)  The thin layer that covers the myometrium of the uterus.
perimysium (34.0K)  The connective tissue that divides a muscle into sections called fascicles.
periodontal ligaments (25.0K)  These structures anchor cementum of each tooth to the jawbone.
periosteum (36.0K)  The membrane that surrounds the diaphysis of a bone.
peripheral nervous system (41.0K)  A system that consists of nerves that branch off the central nervous system.
peristalsis (23.0K)  The rhythmic muscular contractions that move food through the digestive tract.
PET (36.0K)  Position emission tomography; a radiologic procedure that entails injecting isotopes combined with other substances involved in metabolic activity, such as glucose. These special isotopes emit positrons, which a computer processes and displays on a screen.
phalanges (21.0K)  The bones of the fingers.
pharmaceutical (20.0K)  Pertaining to medicinal drugs.
pharmacodynamics (28.0K)  The study of what drugs do to the body: the mechanism of action, or how they work to produce a therapeutic effect.
pharmacognosy (21.0K)  The study of characteristics of natural drugs and their sources.
pharmacokinetics (29.0K)  The study of what the body does to drugs: how the body absorbs, metabolizes,distributes, and excretes the drugs.
pharmacology (20.0K)  The study of drugs.
pharmacotherapeutics (38.0K)  The study of how drugs are used to treat disease; also called clinical pharmacology.
pharyngeal tonsils (27.0K)  Two masses of lymphatic tissue located above the palatine tonsils; also called adenoids.
pharynx (22.0K)  Structure below the mouth and nasal cavities that is an organ of the respiratory system as well as the digestive system.
phenylketonuria PKU (43.0K)  A genetically inherited disorder in which the body cannot properly metabolize the nutrient phenylalanine, resulting in the buildup of phenylketones in the blood and their presence in the urine. The accumulation of phenylketones results in mental retardation.
phlebotomy (22.0K)  The insertion of a needle or cannula (smalltube) into a vein for the purpose of withdrawing blood.
photometer (26.0K)  An instrument that measures light intensity.
physical therapy (24.0K)  A medical specialty that uses cold, heat, water, exercise, massage, traction, and other physical means to treat musculoskeletal, nervous, and cardiopulmonary disorders.
physicians office laboratory POL (100.0K)  A laboratory contained in a physician’s office; processing tests in the POL produces quick turnaround and eliminates the need for patients to travel to other test locations.
physiology (22.0K)  The science of the study of the body’s functions.
pineal body (17.0K)  A small gland located between the cerebral hemispheres that secretes melatonin.
placenta (18.0K)  An organ located between the mother and the fetus. It permits the absorption of nutrients and oxygen. In some cases, harmful substances such as viruses are absorbed through the placenta.
plantar flexion (32.0K)  Pointing the toes downward.
plasma (20.0K)  The fluid component of blood, in which formed elements are suspended; makes up 55% of blood volume.
platelet (29.0K)  Fragments of cytoplasm in the blood that are crucial to clot formation; also called thrombocytes.
pleura (12.0K)  The membranes that surround the lungs.
pleuritis (18.0K)  A condition in which the pleura become inflamed, which causes them to stick together. It can also cause an excess amount of fluid to form between the membranes.
plexus (33.0K)  A structure that is formed when spinal nerves fuse together. It includes the cervical, brachial, and lumbosacral nerves.
pneumothorax (32.0K)  The presence of air or gas in the pleural cavity. The lung typically collapses with pneumothorax.
polar body (17.0K)  A nonfunctional cell that is one of two small cells formed during the division of an oocyte.
polarity (28.0K)  The condition of having two separate poles, one of which is positive and the other, negative.
polarized (19.0K)  The state in which the outside of a cell membrane is positively charged and the inside is negatively charged. Polarization occurs when a neuron is at rest.
polysaccharide (21.0K)  A type of carbohydrate that is a starch.
POMR (40.0K)  The problemoriented medical record system for keeping patients’ charts. Information in a POMR includes the database of information about the patient and the patient’s condition, the problem list, the diagnostic and treatment plan,and progress notes.
postnatal period (31.0K)  The period following childbirth.
postoperative (23.0K)  Taking place after a surgical procedure.
posture (23.0K)  Body position and alignment.
premenstrual syndrome PMS (45.0K)  A syndrome that is a collection of symptoms that occur just before the menstrual period.
prenatal period (24.0K)  The period that includes the embryonic and fetal periods until the delivery of the offspring.
prepuce (21.0K)  A piece of skin in the uncircumcized male that covers the glans penis.
presbyopia (16.0K)  A common eye disorder that results in the loss of lens elasticity. Presbyopia develops with age and causes a person to have difficulty seeing objects close up.
prescribe (19.0K)  To give a patient a prescription to be filled by a pharmacy.
prescription (22.0K)  A physician’s written order for medication.
prescription drug (22.0K)  A drug that can be legally used only by order of a physician and must be administered or dispensed by a licensed health-care professional.
primary germ layer (29.0K)  An inner cell mass that organizes into layers: the ectoderm, mesoderm,and endoderm.
prime mover (23.0K)  The muscle responsible for most of the movement when a body movement is produced by a group of muscles.
primordial follicle (33.0K)  A structure that develops in the ovarian cortex of a female infant before she is born.
proctoscopy (25.0K)  An examination of the lower rectum and anal canal with a 3-inch instrument called a proctoscope to detect hemorrhoids,polyps, fissures, fistulas, and abscesses.
proficiency testing program (37.0K)  A required set of tests for clinical laboratories;the tests measure the accuracy of the laboratory’s test results and adherence to standard operating procedures.
progesterone (26.0K)  A female steroid hormone primarily produced by the ovary.
prolactin (15.0K)  A hormone that stimulates milk production in the mammary glands.
proliferation phase (32.0K)  The second phase of wound healing, in which new tissue forms,closing off the wound.
pronation (26.0K)  Turning the palms of the hand downward.
proofreading (22.0K)  Checking a document for formatting, data, and mechanical errors.
prostaglandin (33.0K)  A local hormone derived from lipid molecules. Prostaglandins typically do not travel in the bloodstream to find their target cells because their targets are close by. This hormone has numerous effects, including uterine stimulation during childbirth.
prostate gland (25.0K)  A chestnut-shaped gland that surrounds the beginning of the urethra in the male.
prostatitis (32.0K)  Inflammation of the prostate gland, which can be acute or chronic.
proteinuria (28.0K)  An excess of protein in the urine.
protozoan (21.0K)  A singlecelled eukaryotic organism much larger than a bacterium; some protozoans can cause disease in humans.
protraction (23.0K)  Moving a body part anteriorly.
proximal (27.0K)  Anatomical term meaning closer to a point of attachment or closer to the trunk of the body.
proximal convoluted tubule (32.0K)  The portion of the renal tubule that is directly attached to the glomerular capsule and becomes the loop of Henle.
psoriasis (36.0K)  A common skin condition characterized by reddishsilver scaly lesions most often found on the elbows, knees, scalp, and trunk.
puberty (20.0K)  The period of adolescence when a person begins to develop secondary sexual traits and reproductive functions.
pubis (24.0K)  The area that forms the front of a hip bone.
pulmonary circuit (25.0K)  The route that blood takes from the heart to the lungs and back to the heart again.
pulmonary function test (37.0K)  A test that evaluates a patient’s lung volume and capacity; used to detect and diagnose pulmonary problems or to monitor certain respiratory disorders and evaluate the effectiveness of treatment.
pulmonary trunk (32.0K)  A large artery that branches into the pulmonary arteries and carries blood to the lungs.
pulmonary valve (26.0K)  A heart valve that is a semilunar valve. It is situated between the right ventricle and the pulmonary trunk.
puncture wound (27.0K)  A deep wound caused by a sharp, pointed object.
pupil (20.0K)  The opening at the center of the iris, which grows smaller or larger as the iris contracts or relaxes, respectively; it regulates the amount of light that enters the eye.
purchase order (22.0K)  A form that authorizes a purchase for the practice.
purchasing group (30.0K)  Groups of medical offices associated with a nearby hospital that order supplies through the hospital to obtain a quantity discount.
pyelonephritis (34.0K)  A jurinary tract infection that involves one or both of the kidneys.
pyrogen (24.0K)  Feverproducing substances released by neutrophils.
quadrant (26.0K)  Four equal sections, such as those into which the abdomen is figuratively divided during an examination.
qualitative test response (44.0K)  A test result that indicates the substance tested for is either present or absent.
quality assurance program (37.0K)  A required program for clinical laboratories designed to monitor the quality of patient care, including quality control, instrument and equipment maintenance, proficiency testing, training and continuing education, and standard operating procedures documentation.
quantitative analysis (40.0K)  In microbiology, a determination of the number of bacteria present in a specimen by direct count of colonies grown on a culture plate.
quantitative test result (38.0K)  The concentration of a test substance in a specimen.
radial artery (20.0K)  An artery located in the groove on the thumb side of the inner wrist, where the pulse is taken on adults.
radiation therapy (31.0K)  The use of x-rays and radioactive substances to treat cancer.
radius (20.0K)  The lateral bone of the forearm.
random urine specimen (32.0K)  A single urine specimen taken at any time of the day; the most common type of sample collected.
random-access memory RAM (68.0K)  The temporary, or programmable, memory in a computer.
range of motion ROM (37.0K)  The degree to which a joint is able to move.
read-only memory ROM (44.0K)  A computer’s permanent memory, which can be read by the computer but not changed. It provides the computer with the basic operating instructions it needs to function.
reagent (22.0K)  A chemical or chemically treated substance used in test procedures and formulated to react in specific ways when exposed under specific conditions.
recovery position (30.0K)  The position a person is placed in after receiving first aid for choking or cardiopulmonary resuscitation.
rectum (29.0K)  The last section of the sigmoid colon that straightens out and becomes the anal canal.
reference (14.0K)  A recommendation for employment from a facility or a preceptor.
reference laboratory (28.0K)  A laboratory owned and operated by an organization outside the physician’s practice.
reflex (32.0K)  A predictable automatic response to stimuli.
refraction examination (30.0K)  An eye examination in which the patient looks through a succession of different lenses to find out which ones create the clearest image.
refractometer (28.0K)  An optical instrument that measures the refraction, or bending, of light as it passes through a liquid.
relaxin (23.0K)  A hormone that comes from the corpus luteum. It inhibits uterine contractions and relaxes the ligaments of the pelvis in preparation for childbirth.
renal calculi (34.0K)  Kidney stones.
renal column (21.0K)  The portion of the renal cortex between the renal pyramids.
renal corpuscle (34.0K)  Corpuscle that is composed of the glomerulus and the glomerular capsule. The filtration of blood occurs here.
renal cortex (25.0K)  The outermost layer of the kidney.
renal medulla (34.0K)  The middle portion of the kidney.
renal pelvis (24.0K)  The internal structure of the kidney. Urine flows from the renal pelvis down the ureter.
renal pyramids (40.0K)  Triangular-shaped areas in the medulla of the kidney.
renal sinus (23.0K)  The medial depression of a kidney.
renal tubule (33.0K)  Structure that extends from the glomerular capsule of a nephron and is comprised of the proximal convoluted tubule, the loop of Henle, and the distal convoluted tubule.
renin (13.0K)  A hormone secreted by the kidney that helps to regulate blood pressure.
repolarization (26.0K)  The process of returning to the original polar (resting) state.
reputable (24.0K)  Having a good reputation.
requisition (21.0K)  A formal request from a staff member or doctor for the purchase of equipment or supplies.
respiratory volume (30.0K)  The different volumes of air that move in and out of the lungs during different intensities of breathing. These volumes can be measured to assess the healthiness of the respiratory system.
retina (11.0K)  The inner layer of the eye; contains light-sensing nerve cells.
retraction (23.0K)  Moving a body part posteriorly.
retrograde pyelography (43.0K)  A radiologic procedure in which the doctor injects a contrast medium through a urethral catheter and takes a series of x-rays to evaluate function of the ureters, bladder,and urethra.
retroperitoneal (39.0K)  An anatomical term that means behind the peritoneal cavity. It is where the kidneys lie.
Rh antigen (23.0K)  A protein first discovered on the red blood cells of rhesus monkeys, hence the name Rh.
rhabdomyolysis (33.0K)  A condition in which the kidneys have been damaged due to toxins released from muscle cells.
RhoGAM (33.0K)  A medication that prevents an Rh-negative mother from making antibodies against the Rh antigen.
RNA (27.0K)  A nucleic acid used to make protein.
rods (21.0K)  Light-sensing nerve cells in the eye, at the posterior of the retina, that function in dim light but do not provide sharp images or detect color.
rosacea (23.0K)  A condition characterized by chronic redness and acne over the nose and cheeks.
rotation (33.0K)  Twisting a body part.
route (12.0K)  The way a drug is introduced into the body.

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