Para-aminohippuric acid, or PAH, passes completely through the glomerular membrane. During filtration of blood by the kidneys, only about 1/10 of the original PAH in the plasma remains in the plasma. Therefore, PAH clearance can be used for estimating the flow of plasma through the kidneys.
P-QRS-T refers to the distinct points of a complete cardiac cycle seen on the electrocardiogram strip. The P wave is the depolarization or activation of the atria. The QRS wave is the depolarization or activation of the heart's ventricles. The T wave is the recovery of the ventricles or the depolarization of the ventricles.
Pallor describes a condition in which the skin color becomes pale; it usually accompanies the onset of a change in physiology (shock, illness, etc.).
Palpation is a technique used in physical examinations in which the examiner feels the texture, size, consistency, and location of a certain part of the body with the hands.
The pancreas is a gland about 15 cm long, that lies behind the stomach. One end touches the curve of the duodenum; the other end touches the spleen. It is composed of clusters of cells which are involved in the digestive process. The pancreas is also the gland that produces insulin.
One way to create a microgravity environment in which a plane climbs rapidly at a 45 degree angle, traces a parabola, and then descends at a 45-degree angle. During the parabola, the contents of the plane experience free fall or weightlessness.
Parainfluenza virus is a member of the genus Paramyxovirus. Parainfluenza can cause acute laryngotracheitis and croup in children and respiratory infections in adults.
A paramecium is an aquatic, oval-shaped single-celled microscopic organism that moves by means of hair-like projections called cilia. Paramecia are members of the Protozoan family, a group of the most primitive forms of animal life.
A parasite is an organism that lives on or in and draws nourishment from another organism.
Parasternal means alongside the sternum.
Parathormone (PTH) also called parathyroid hormone, is a peptide hormone formed by the parathyroid glands that raises the serum calcium when administered parenterally (other than via the digestive tract) by causing bone resorption.
Parathyroid hormone (PTH)
Parathyroid hormone (a.k.a. parathormone, PTH) is a hormone, synthesized and released by the parathyroid glands, that controls the distribution of calcium and phosphate in the body.
Parenchyma is the tissue characteristic of an organ, as distinguished from connective tissue.
A parietal cell (oxyntic cell) is a cell of the gastric glands that secretes hydrochloric acid in the lower region of the stomach to aid in digestion.
Parotid means situated near the ear. It usually refers to the parotid salivary gland.
The parotid gland is the largest of the salivary glands situated below and in front of the ear, on either side. It discharges through the parotid duct.
A passive payload on the Space Shuttle, or other space vehicle, does not require any crew time or astronaut interaction to operate, except possibly for the need to be activated, placed in a certain position or shut down.
Pasteurization is the process of applying heat, usually to milk or cheese, for a specific period of time for the purpose of killing or retarding the development of pathogenic bacteria.
Patella, also called the knee cap, is a flat triangular bone at the front of the knee joint, having a pointed apex that attaches to the ligamentum patellae.
Pathogens are organisms which cause disease or illness upon entering the body.
Pathogenic means causing disease or abnormality.
Pathology is the study of disease processes with the aim of understanding their nature and causes. This is achieved by observing samples of blood, urine, feces, and diseased tissue obtained from the living patient or from an autopsy, by the use of X-rays and by many other techniques.
Paucity means fewness, smallness of number, or scarcity.
Penicillin is any one of a group of antibiotics derived from cultures of species of the fungus penicillium or produced semisynthetically. Administered orally or parenterally, it is used to prevent or treat a wide variety of diseases and infections.
Pepsin is an enzyme in the stomach that begins the digestion of proteins by splitting them into smaller pieces.
A peptide is any group of compounds consisting of two or more amino acids linked by chemical bonding. Peptides in the human body can take the function of hormones (e.g. antidiuretic hormone),can form proteins, or may have functions in the digestive process (and therefore may be found throughout the body - in the digestive tract, blood, cells and tissues).
Perceptual reactions are based on the interpretation of sensory information, using both the data detected by the senses (at the moment) and previous experience.
A perceptual reaction is based on perception, the process by which information about the world, received by the senses, is analyzed and made meaningful.
Perfusion is the passage of fluid through a tissue. It can refer to the passage of blood through the lung tissue to pick up oxygen from the air in the alveoli and the release of carbon dioxide. Or, perfusion can refer to the deliberate introduction of fluid into a tissue, usually by injection into the blood vessels supplying the tissue.
Periosteal refers to the periosteum, a layer of dense connective tissue that covers most of the surface of a bone, providing attachment for muscles, tendons and ligaments.
The periosteum is a layer of dense connective tissue that covers most of the surface of a bone, providing attachment for muscles, tendons and ligaments.
Peripheral means relating to or situated near the outer part of the body or organ in relation to a specific reference point.
Peripheral cardiovascular system
Peripheral cardiovascular system refers to the part of the cardiovascular system (distinguished from the heart and the pulmonary circulation) that supplies blood to all the tissues of the body except the lungs. It includes arteries, arterioles, veins, venules, and capillaries.
Peripheral mononuclear cell
Peripheral mononuclear cells are monocytes and lymphocytes which circulate in the bloodstream.
Peripheral resistance is the resistance to blood flow caused by constriction of the systemic blood vessels in the large veins of the legs and arms, building up venous blood pressure which usually reaches 4 to 7 mmHg.
Peripheral Venous Pressure (PVP)
Peripheral venous pressure is the blood pressure in the peripheral veins, usually about 4 to 7 mm Hg; this pressure is due to the considerable resistance to blood flow in the large veins.
The periphery is the outermost part or region within a precise boundary.
Peritonitis is the inflammation of the sac that lines the abdominal cavity.
Peroxidation is the act of an enzyme, called peroxidase, catalyzing the oxidation of various substances in the presence of hydrogen peroxide, usually converting to water in the process.
Personal Digital Assistant (PDA)
A personal digital assistant is a hand-held computer device that may be used to enter, manipulate, and/or display data.
A perturbation is a disturbance or abnormality.
Pertussis means whooping cough, an infectious disease caused by Bordetella pertussis and characterized by recurrent bouts of spasmodic coughing.
A petri dish is a small, shallow circular dish made of thin glass or clear plastic with a loosely fitting, overlapping cover. It is used especially in microbiology for the growing of microorganisms on solid media.
pH indicates the acidity of a substance. A pH below 7 is acid, a pH above 7 is alkaline and a pH of 7 is neutral.
A phage, also called bacteriophage, is a virus that infects and ultimately destroys bacterial cells. These viruses are normally present in sewage and body products.
Phagocytic cells are white blood cells that protect the body against invading microorganisms by engulfing the organism and then destroying it with digestive enzymes.
Phagocytosis is the process whereby materials are surrounded and taken into a cell by invagination of the plasma membrane.
The phalanges, or bones of the fingers (or toes), number 14 in each hand (foot). A single bone of the finger (or toe) is referred to as a phalanx. There are two phalanges in the thumb and three phalanges in each of the other fingers. In order from the thumb, the fingers are commonly referred to as the index finger, middle finger, ring finger, and little finger. In medical terminology, the fingers (starting with the thumb) are referred to as 1, 2, 3, 4, and 5. When referring to a specific phalanx on a finger (or toe) it is common to refer first to the finger number, then to the position of the phalanx in question on the finger. For example, phalanx 3-1 refers to the tip of the third finger (middle finger). Phalanges 5-2 refers to the middle bone of the little finger.
A phalanx is a bone of a finger or toe.
A phantom is a device used in radiation biology to estimate the effects of radiation. It simulates the properties of body tissues with respect to deposition of radiation or radioactive material in them.
Pharmaceutical refers to man-made and natural drugs used to treat diseases, disorders, and illnesses.
Pharmacodynamics is the study of drug action on living organisms.
Pharmacokinetics refers to the study of the metabolism and action of drugs, with particular emphasis on the time required for absorption, duration of action, distribution in the body, and excretion.
Pharmacologic means pertaining to the science of drugs, including their composition, uses and effects.
Pharmacology is the science of the properties of drugs and their affects on the body.
The pharyngeal vault is the upper portion or roof of the rhinopharynx.
Pharyngitis is the inflammation of the mucous membrane and underlying parts of the pharynx.
Phase refers to a discrete uniform part of a material substance that can be separable from the rest. For example, water can exist in three separate phases: solid (ice), liquid, and vapor.
A phase shift implies a change from the time location associated with a biological rhythm peak or trough. For example, the body temperature of a healthy person is usually lowest (trough) around 9 AM and highest (peak) about 7 PM. A person who works at night and therefore lives a schedule which is basically opposite from the general population, will have the trough body temperature reading in the evening and a peak in the morning - a phase shift of roughly 180 degrees.
The phase-contrast microscope is a specially constructed microscope that has a special condenser and objective containing a phase-shifting ring. Small differences in index of refraction are made visible as intensity or contrast differences in the image; it is particularly useful for examining structural details in transparent specimens such as living or unstained cells and tissues.
Phenol is a highly poisonous, caustic crystalline chemical compound derived from coal tar or plant tar or manufactured synthetically. It has a distinctive, pungent odor and, in solution, is a powerful disinfectant.
A phenotype is the visible properties of an organism that are produced by the interaction of the genes and the environment.
Phenylephrine is a chemical used as a drug that constricts blood vessels. It is given by injection to increase blood pressure, in a nasal spray to relieve nasal congestion, and in eye drops to dilate the pupils.
Phlebotomy is the puncture or surgical opening of a vein in order to remove blood or to infuse fluids, blood or drugs in the treatment of many conditions.
A phonocardiogram is a recording of heart sounds which leaves a permanent record in the form of a tracing recorded on paper.
Phosphate is a salt of phosphoric acid. Phosphates are extremely important in living cells, particularly in the storage and use of energy and the transmission of genetic information within a cell and from one cell to another.
The word phosphene is derived from two Greek words "phos", light, and "phainein", to show. A phosphene is the conscious sensation of having perceived light, colored or colorless, patterned or unstructured, on stimulation of a personÉs visual apparatus by some manner other than exogenous light impinging on the retina. There are many types of phosphenes, including pressure, electrical, magnetic, and x-ray phosphenes. The best known phosphene is the pressure phosphene which consists of light sensations induced by pressure on the closed, but not necessarily dark adapted, human eye (i.e., by rubbing the eyes in the dark). These are also known as deformation phosphenes. As is true for all categories of phosphenes, there is a high degree of individuality and, in fact, some individuals perceive multicolored kaleidoscope-like patterns, whereas others see nothing on pressure to the eyeball.
Phosphofructose kinase is an enzyme found in cells that participates in glucose metabolism.
Phosphoglyceric kinase is an enzyme found in cells that participates in glucose metabolism by transferring a inorganic phosphate from 1,3 bisphosphoglycerate to adenosine diphosphate to form 3-phosphoglycerate and the energy generating compound, adenosine triphosphate.
A phospholipid is a lipid (fat) containing phosphorus.
Phosphorus is a nonmetallic element. Phosphorus compounds are major constituents in the tissues of both plants and animals. In man, phosphorus is mostly concentrated in bone. Some phosphorus-concentrated compounds play an important part in energy conversions and storage in the body. In a pure state, phosphorus is toxic.
A photoelectric cell is an electronic device whose electrical properties are modified by the action of light.
Photogrammatic means pertaining to three-dimensional multispectral mapping of the earth's surface. The images provide information about the maturity of crops, attacks on crops by pests, effects of pollution (forest, air and water) and many other conditions.
Photometric means a more precise measurement of the brightness of light, which can be digitized and calibrated; a measure of the intensity of light.
A photomotograph is a device used to determine reflex time by measuring movement in a particular limb as a reflex is initiated. The device uses a beam of light directed at a photovoltaic cell to measure the displacement of the limb as it moves during the reflex. Movement is detected by the beam of light and registered as a change in photocell voltage. The change in voltage is then recorded on paper to give a time-position plot of reflex action.
Photon refers to the smallest quantity of electromagnetic energy.
Photosynthesis is the process by which green plants use the energy of light and a special substance called chlorophyll to synthesize carbohydrates (energy) from carbon dioxide and water.
Phototropism is the response of an organism to light, usually expressed as movement of a part of an organism toward or away from the stimulus of light, as when trees or plants grow toward sunlight.
A photovoltaic cell is a type of photoelectric cell that generates a voltage when a light beam falls on the boundary between two dissimilar substances within the cell.
Physiologic means of or relating to physiology, the science that studies the function of the body and the vital processes of living things, whether animal or plant.
Physiological means of or relating to physiology, the science that studies the function of the body and the vital processes of living things, whether animal or plant.
Physiology is the study of the functions or vital processes of living things, whether animal or plant.
Phytohemagglutinin (PHA) is a mitogen from plants that stimulates the activation of lymphocytes, causing red blood cells to adhere or clump.
Phytomitogen is a mitogenic lectin causing lymphocyte transformation accompanied by mitotic proliferation of the resulting blast cells identical to that produced by antigenic stimulation. Phytohemagglutinin and concanavalin A are phytomitogens.
Pilocarpine hydrochloride ophthalmic solution
Pilocarpine hydrochloride ophthalmic solution is a medication commonly used to treat glaucoma; it constricts the pupil and reduces pressure in the eye.
Pitch refers to the vertical (up and down) axis or plane of an object.
The pituitary gland (a.k.a. hypophysis) is the master endocrine gland -- though it is about the size of a pea -- located beneath the hypothalamus in a bony cavity at the base of the skull. Its secretes many hormones, including thyroid-stimulating hormone, adrenocorticotropic hormone (ACTH), gonadotropins, growth hormone, prolactin, lipotropin, melanocyte-stimulating hormone, antidiuretic hormone (ADH), and oxytocin.
A receptor is a structural protein molecule on the cell surface or within the cytoplasm that binds to a specific factor, such as a hormone from the pituitary gland in the case of pituitary receptors.
A pixel is a single volume element of the display of the computer terminal image.
Thus far, plant biology research in NASA has focused primarily on understanding the mechanism of gravity sensing and transduction at the cellular and subcellular levels, the dramatic modifications of plant form and size that occur when plants are vibrated, the interaction of light with gravitropism, plant growth, development, and metabolism. Microgravity has been reported to affect such areas as plant morphology, directional growth, flowering, cell division and differentiation, and chromosomal integrity, and to cause changes in organelle functioning and cellular processes.
Plant growth chamber
The Svet plant growth chamber is a rectangular metal enclosure with windows on the front and on the right side of chamber walls for visual inspections by crewmembers and performance of experimental procedures. Reflective film has been applied to the interior walls of the chamber to intensify illumination, thereby facilitating growth conditions for the plants.
Plantar relates to the sole of the foot.
The plantar flexor is a group of muscles that bend the toes (or finger) downward, towards the sole (or palm).
Plantarflexion is the bending of the toes (or fingers) downward, toward the sole (or palm).
The plantaris is a muscle of the lower leg that is used to flex the foot.
Plasma is the fluid portion of blood. It consists of a solution of various inorganic salts, such as sodium, potassium and calcium, and protein, as well as other trace substances.
The plasma membrane is the membrane which separates the inside of the red blood cells from the surrounding plasma.
Plasma volume is the measure of the volume of plasma in the blood. Plasma is the liquid portion of blood; the solid portion of blood is composed of cells. Plasma consists of a solution of various inorganic salts, such as sodium, potassium, calcium, protein, and other trace substances. Normal plasma volume in an average adult is usually 3 liters, while total blood volume is about 5 liters.
Plasmid is a structure in cells consisting of DNA that can exist and replicate independently of the chromosomes. In organisms (other than man) that have been studied, it appears that plasmids interfere with gene activity.
Plasmin is a trypsin-like serine protease that is responsible for digesting fibrin in blood clots. It is generated from plasminogen by the action of another protease, lasminogen activator.
Plasminogen is an inactive precursor of plasmin; it occurs at 200 mg/l in blood plasma.
Plastic nuclear track detectors
Plastic nuclear track detectors are devices that measure radiation. They usually contain plastic nuclear track detectors, pieces of plastic wedged between a crystalline surface. As the radioactive particles impact the crystalline surface, they bounce off and scar the surface of the plastic by making tracks.
A platelet is a disk-shaped structure present in the blood; they have several functions, all relating to stopping bleeding.
A plethysmograph is a device for measuring and recording changes in volume of a part, organ, or whole body.
Pleural effusion is an abnormal accumulation of fluid in the intrapleural spaces of the lungs, characterized by fever, chest pain, dyspnea and nonproductive cough.
Pneumatic means inflated or operated by air (pressure).
A pneumatic cuff is a device that is inflated and deflated by air entering and exiting from it. It is commonly used in the measuring of blood pressure in humans by inflating and compressing the upper arm (or thigh) with a blood pressure cuff.
A pneumograph is an instrument used to record respiratory rate from movements on the body surface.
Pneumography is the measure of respiratory movements during respiration (e.g. respiratory rate) with an instrument called a pneumograph.
Pneumonitis is an inflammation of the lungs. It may be caused by a virus or may be a hypersensitivity reaction to chemicals or organic dusts, such as bacteria, bird droppings, or mold. Dry cough is usually a symptom. Treatment depends on the cause but includes removal of any offending agents and the administration of corticosteroids to reduce inflammation.
A pneumotachograph is an instrument used to measure the instantaneous flow of respiratory gases.
Polar orientation refers to the process of aligning or positioning in a three-dimensional space with respect to a polar reference system. A polar reference system aligns with either of two extremities of an axis through a sphere, such as the Earth's North and South poles.
Poliomyelitis is the inflammation of the gray matter of the spinal cord.
Pollen is the powdery, yellowish grain derived from seed plants that develops into the male reproductive cell.
A pollutant is something that makes another (such as air, water or soil) unfit, harmful, or impure.
Polymerase Chain Reaction
Polymerase Chain Reaction, or PCR, is a process which permits scientists to make unlimited copies of genes. This is done with a single molecule of DNA. One hundred billion copies of the DNA can be generated in a few hours. This technique is used to investigate and diagnose bacterial diseases, viruses associated with cancer, and genetic diseases such as diabetes mellitus.
Polymorphonuclear leukocytes are large granular white blood cells whith multi-lobed nuclei (namely neutrophils, basophils and eosinophils) that have the capacity for phagocytosis (destruction by ingestion) of foreign cells and materials. In addition, these cells, when stimulated, can degranulate and release chemicals such as histamine into the blood stream.
Polyp is a general descriptive term used with reference to a mass of tissue that bulges or projects outward, or upward from the normal surface level. Polyps are also a larval form of some invertebrates, such as jellyfish.
A polysaccharide is a carbohydrate formed from many monosaccharides (simple sugars) joined together in long linear or branched chains. Polysaccharides have two important functions: (1) as a storage form of energy (glycogen in man) and (2) as structural elements of cells.
Polysomnography is the continuous and simultaneous monitoring of relevant normal and abnormal physiological activity during sleep.
The pons varolii (or pons) is the part of the brain stem that links the medulla oblongata and the thalamus, bulging forward in front of the cerebellum, from which it is separated by the fourth ventricle. It contains numerous nerve tracts between the brain and the spinal cord.
The popliteal nerve is the larger of the two terminal branches of the sciatic nerve which descends along the back part of the thigh, behind the knee, and on to the soleus (calf muscle).
Posterior describes or relates to the back (or dorsal) portion of the body.
Postural means relating to or effected by posture. Posture is defined as the position of the limbs or the carriage of the body as a whole.
Postural equilibrium is a reflexive mechanism which anticipates changes in body orientation when the body becomes off balance and makes appropriate adjustments of the body to prevent falling; such as, when the body is suddenly pushed to the right, even before it can fall, the right leg extends instantaneously in a reflexive motion.
Potable means water that is fit to drink.
Potassium is the principal cation (positively charged ion) in intracellular fluid and is of primary importance in its maintenance. Proper balance of potassium, calcium and magnesium ions are essential for the normal function of muscles.
Potassium gluconate is another name for gluconic acid potassium salt and is used in hypokalemia as a potassium replenisher.
Potassium-40 is a naturally occurring radioactive potassium isotope. It exists as 0.0119 percent of all potassium in the body and is the primary source of natural radioactivity in living tissue.
Potassium-42 is an artificial potassium isotope with a half life of 12.47 years which is used as a tracer in studies of potassium distribution in body fluid compartments.
A potentiometer is an instrument used to determine the precise measurement of electromotive forces by which a part of the voltage to be measured is balanced against that of a known electromotive force and computed therefrom by the law of fall of potential.
A precipitant solution is a solution that usually contains salts which pass through a semi-permeable membrane and cause protein molecules in a solution to become a solid.
Precordial means of or pertaining to the precordium, which forms the region over the heart and lower abdomen.
Prednisone is a glucocorticoid that is prescribed in cases of severe inflammation and immunosuppression.
Predominance means exhibiting a superiority in weight, quantity, power, or importance.
Pregnanediol is a crystalline, biologically inactive compound found in the urine of women during pregnancy or in the secretory phase of the menstrual cycle. A dihydroxyl derivative of the saturated steroid pregnane, this compound is formed by the reduction of progesterone.
Premature atricular contractions
Often, a small area of the heart becomes much more excitable than normal and causes an abnormal impulse to be generated during the time interval between the normal impulses. This initiates a premature contraction of the atria of the heart. This can result from a local area of muscle ischemia, overuse of stimulants such as caffeine or nicotine, lack of sleep, anxiety or other debilitating states.
Premature ventricular contractions
Often, a small area of the heart becomes much more excitable than normal and causes an abnormal impulse to be generated during the time interval between the normal impulses. This initiates a premature contraction of the ventricles of the heart. This can result from a local area of muscle ischemia, overuse of stimulants such as caffeine or nicotine, lack of sleep, anxiety or other debilitating states.
Presyncopal relates to the symptoms of syncope, such as lightheadedness, sweating and blurred vision.
Presyncope is characterized by symptoms and signs indicative of imminent syncope (a lapse into unconsciousness caused by transient cerebral hypoxia).
The Priroda module is the latest module added to the Mir Space Station. It docked with Mir during the Mir 21 mission, and is now configured as a laboratory where Earth observation and microgravity research is being conducted.
A probe is an instrument used to investigate an unknown configuration, condition, or region.
Procto-sigmoidoscopy is the examination of the rectum and sigmoid by means of the sigmoidoscope, an instrument which allows for the direct visualization of the mucous membrane lining the colon.
A progenitor is an ancestor or precursor.
Progenitor cells are cells found in the bone marrow with the potential of maturing into multiple cell types depending on the environment and growth factors.
Progress is the name given to an unmanned Russian transport vehicle which docks to the Mir Space Station, delivering food and supplies when needed.
Proliferation means to reproduce or increase rapidly and repeatedly.
A segment of DNA which "drives" gene expression. It usually lies upstream (5') of a gene. A promoter aligns the RNA polymerase so that transcription will initiate at a specific site.
Prophylactic is an agent that prevents the spread of disease.
Proprioceptive function is the activity relating to a proprioceptor, a specialized sensory nerve ending that monitors internal changes in the body brought about by movement and muscular activity. Proprioceptors located in muscles and tendons transmit information that is used to coordinate muscular activity.
The proprioceptive system is made up of specialized sensory nerve endings that monitor internal changes in the body brought about by movement and muscular activity. Proprioceptors located in muscles and tendons transmit information that is used to coordinate muscular activity.
A proprioceptor is a specialized sensory nerve ending that monitors internal changes in the body brought about by movement and muscular activity. Proprioceptors located in muscles and tendons transmit information that is used to coordinate muscular activity.
Prostaglandins are one of a group of hormone-like substances present in a wide variety of tissues and body fluids; they have many actions, such as dilation and constriction of veins, stimulation of intestinal muscles, and contraction of uterine muscle.
A prostatic massage is the manual expression of prostatic secretions by digital rectal technique. It is also usedto treat various congestive and inflammatory prostatic conditions by the emptying the prostatic sini and ducts by repeated downward compression maneuvers.
A prosthesis (plural prostheses) is any artificial device that is attached to the body as an aid. Prostheses include dentures, artificial limbs, hearing aids and implanted pacemakers.
Protease is an enzyme that causes the decomposition of protein.
Proteins are one of a group of organic compounds of carbon, hydrogen, oxygen and nitrogen with sulfur and phosphorus possibly present. The protein molecule is a complex structure made up of one or more chains of amino acids, which are linked by peptide bonds. Proteins are essential constituents of the body; they form the structural material of muscles, tissues, organs, etc. and are equally important as regulators of function as enzymes and hormones; they can also be converted into glucose and used as an energy source by the body.
Protein crystal growth
When a protein solution and a salt solution are brought together, protein crystal growth starts. Under microgravity conditions the crystals grow much larger and more highly ordered than under 1g conditions.
Protein metabolism is the process of production, use, and excretion of protein in the human body. Proteins are essential chemical substances that the body uses in many processes, including energy production. Proteins form the structural material of muscle, tissue, organs, and when they make up enzymes and hormones, they also regulate the function and behavior of other cells.
Protein synthesis is the process of anabolic metabolism (simple substances converted into more complex compounds) that forms new proteins.
Protista, a Greek word meaning "primitive" or "first," is the third kingdom in the classification of life forms. Protista consists of single-celled microbes -- such as algae, bacteria, fungi, and protozoa -- and multicellular organisms that are not differentiated (organized) into distinct tissues and organs, as are higher animals and plants.
A proton is a positively-charged particle forming the nucleus of hydrogen and present in the nuclei of all elements.
A provocative move is one which will induce, or cause, certain symptoms or effects.
Proximal means anatomically situated close to the origin or point of attachment, or close to the median, or middle, line of the body.
Psig is an abbreviation for pounds per square inch
The psoas is one of two muscles that run from the spine to the top of the upper leg bone and act to flex the lower back and thigh.
Psychiatry is the study of mental disorders and their diagnosis, management and prevention.
Psychiatry is the medical specialty concerned with the prevention, treatment and study of mental, emotional and behavioral disorders.
Psychology is the science concerned with the behavior of man and animals.
Psychosomatic pertains to the relationship of the mind and body.
Puffy face syndrome
"Puffy face syndrome" refers to the swollen appearance of the face caused by the redistribution of body fluids from the lower body to the upper body. In space, this occurs due to the lack of downward gravitational forces in microgravity.
Pulmonary relates to the lungs.
Pulmonary blood volume
Pulmonary blood volume is the volume of blood in the lungs.
Pulmonary capillary blood flow
Pulmonary capillary blood flow is the measure of the rate of blood flow in the capillaries of the lungs.
Pulmonary diffusing capacity
Pulmonary diffusing capacity is the diffusion capacity of oxygen and carbon dioxide through the lung tissue.
Pulmonary function is the ability of the lungs to exchange oxygen and carbon dioxide.
Pulmonary physiology is the research area which focuses on studying the lungs.
Pulmonary ventilation is the passage of air into and out of the respiratory tract.
Pulsatile means throbbing or beating rhythmically.
Pulse pressure is the calculated difference between the systolic and diastolic blood pressure measurements.
Pulse rate is the number of heart beats per minute.
Pulsing is a method of moving that is used by the jellyfish.
Purification is the act or process of cleansing.
Pyelonephritis is an inflammation of the renal parenchyma, calyces and pelvis particularly due to a local bacterial infection.
Pyemia is a systemic disease caused by the multiplication of pyogenic (pus forming) organisms causing multiple abscesses.
Pyramidal neurons are a type of neuron found in the cerebral cortex of the brain and have pyramid-shaped cell bodies.
Pyruvate kinase is an enzyme found in cells that participates in glucose metabolism by transferring an inorganic phosphate from phosphoenolpyruvate to adenosine diphosphate to form pyruvate and the energy generating compound, adenosine triphosphate.
Pyruvate oxidation refers to the act of oxidizing pyruvic acid via a complex series of reactions in the Krebs cycle to yield carbon dioxide and energy in the form of ATP (adenosine triphosphate).