Chapter 8 Anatomy and Physiology: Vital Vocabulary Flashcards
The commonly used blood classification system, based on the antigens present or absent in the blood
ABO system
The muscles not normally used during quiet breathing; examples include the sternocleidomastoid muscles of the neck, the chest pectoralis major muscles, and the abdominal muscles
accessory muscles
The ability of the lens of the eye to change its shape to focus on a close object
accommodation
The socket formed by the coxal (hip) bone into which the ball-shaped femoral head fits snugly
acetabulum
A neurotransmitter released at synapses within the autonomic nervous system and by motor neurons to stimulate skeletal muscle contraction
acetylcholine (ACh)
An enzyme found in the central nervous system, in red blood cells, and in motor endplates of skeletal muscle that causes the decomposition of acetylcholine
acetylcholinesterase
Any molecule that can give up a hydrogen ion, and therefore increases the concentration of hydrogen ions in a water solution
acid
A pathologic condition resulting from the accumulation of acids in the body (blood pH less than 7.35)
acidosis
The tip of the shoulder and the site of attachment for the clavicle and various shoulder muscles
acromion process
Sequence of changes in the membrane potential that occurs when an excitable cell (neuron or muscle) is stimulated
action potential
A contractile protein found in the thin filaments of skeletal muscle cells
actin
A method used to move compounds across a cell membrane to create or maintain an imbalance of charges, usually against a concentration gradient and requiring the expenditure of energy
active transport
The temporary or permanent reduction of sensitivity to a particular stimulus
adaptation
The nucleotide formed from the metabolism of nutrients in the cell; involved in energy metabolism; used to store energy
adenosine triphosphate (ATP)
The outer layer of the adrenal gland; it produces hormones that are important in regulating the water and salt balance of the body
adrenal cortex
Paired endocrine glands located on top of the kidneys that release epinephrine and norepinephrine when stimulated by the sympathetic nervous system; each adrenal gland consists of an inner adrenal medulla and an adrenal cortex
adrenal glands
Having the characteristics of the sympathetic division of the autonomic nervous system
adrenergic
Hormone that targets the adrenal cortex to secrete cortisol (a glucocorticoid)
adrenocorticotropic hormone (ACTH)
Metabolism that can proceed only in the presence of oxygen
aerobic metabolism
The perception that a stimulus is still present after the stimulus has been removed
afterimage
The pressure in the aorta against which the left ventricle must pump blood
afterload
The smallest of plasma proteins; they make up around 60% of the plasma proteins and are responsible for the oncotic pressure in the vasculature, thereby controlling the movement of water into and out of the circulation.
albumins
A hormone responsible for the reabsorption of sodium and water from the kidney tubules
aldosterone
A pathologic condition resulting from the accumulation of bases in the body (blood pH greater than 7.45)
alkalosis
Variant forms of a gene, which can be identical or slightly different in a sequence of deoxyribonucleic acid
alleles
The air sacs of he lungs in which the exchange of oxygen and carbon dioxide takes place; also, the bony sockets for the teeth that reside in the mandible and maxilla
alveoli (singular, alveolus)
The building of larger substances from smaller substances, such as the building of proteins from amino acids
anabolism
Metabolism that occurs in the absence of oxygen
anaerobic metabolism
The study of the structure of an organism and its parts
anatomy
A prominence of the sternum that indicates the point where the second rib joins the sternum; also called the sternal angle or manubriosternal junction
angle of Louis
A molecule that blocks the ability of a given chemical to bind to its receptor, preventing a biologic response
antagonist
Proteins, polysaccharides, glycoproteins, or glycolipids commonly found on the surfaces of red blood cells that stimulate an immune system response and cause formation of antibodies; cells learn to recognize antigens as either “self” or “nonself” (foreingn
antigens
The principal artery leaving the left side of the heart and carrying freshly oxygenated blood to the body; the largest artery in the body
aorta
The semilunar valve that regulates blood flow from the left ventricle to the aorta
aortic valve
A portion of the pons that is thought to work with the pontine respiratory group to regulate the length and depth of inspiration
apneustic center
The portion of the skeletal system made up of the upper extremities, shoulder girdle, pelvic girdle, and lower extremities
appendicular skeleton
Watery fluid filling the anterior eye cavity; the quantity determines the intraocular pressure, which is critical to sight
aqueous humor
A type of loose connective tissue that binds skin to underlying organs and fills in spaces between muscles
areolar tissue
Six paired cartilages stacked on top of each other in the larynx
arytenoid cartilages
Condition where parts of the image are out of focus and others are in focus; caused by irregularities in the shape of the eye lens
astigmatism
The first cervical vertebra (C1), which provides support for the head
atlas
The two upper chambers of the heart
atria (singular, atrium)
A hormone produced by the atria when they are distended by increased blood volume; it inhibits the absorption of water and sodium in the renal tubules, thereby increasing the elimination of water
atrial natriuretic peptide
A group of cells that conduct an electrical impulse through the heart; located in the floor of the right atrium immediately behind the tricuspid valve and near the opening of the coronary sinus
atrioeventricular (AV) node
The mitral and tricuspid valves through which blood flows from the atria to the ventricles
atrioventricular (AV) valves
Ability of cardiac pacemaker cells to initiate an electrical impulse spontaneously without being stimulated from another source (such as a nerve)
automaticity
A subdivision of the nervous system that controls primarily involuntary body functions; comprised of the sympathetic and parasympathetic nervous systems.
autonomic nervous system (ANS)
The chromosomes that do not carry genes that determine sex.
autosomes
The portion of the skeleton made up of the skull, thoracic cage, and vertebral column.
axial skeleton
Imaginary line joining the positive and negative electrodes of a lead; also the second cervical vertebra.
axis
Long, slender extension of a neuron (nerve cell) that conducts electrical impulses away from the nerve cell body to adjacent cells.
axon
Lymphocytes that exist in the blood, and are abundant in the lymph nodes, bone marrow, intestinal lining, and spleen; also called B cells.
B lymphocytes
Nerve endings that are stimulated by pressure; they are located in the aortic arch and carotid sinuses.
baroreceptors
Structures located deep within the cerebrum, diencephalon, and midbrain that have an important role in coordination of motor movements and posture.
basal ganglia
The rate at which nutrients are consumed in the body.
basal metabolic rate
White blood cells that contain histamine granules and other substances that are released during inflammatory and allergic responses.
basophils
A waste product of red blood cell destruction that undergoes further metabolism in the liver.
bilirubin
The merging of two images into one.
binocular vision
A layer of tightly-adhered cells that protects the brain and spinal cord from exposure to medications, toxins, and infectious particles.
blood-brain barrier
Soft tissue that fills the inside of bones and is the site of production of red blood cells, platelets, and most white blood cells.
bone marrow
The collection of hollow in the bone of the inner ear that provide protection to the structures of the inner ear from damage and from extraneous of stimulation.
bony labyrinth
Gas law that demonstrates that as pressure increases, volume decreases; at a constant temperature, the volume of gas is inversely proportional to its pressure (if the pressure on a gas is doubled, then its volume is halved); written as PV=K, where P= pressure, V=volume, and K= a constant.
Boyle’s law
The part of the central nervous system located within the cranium; contains billions of neurons that serve a variety of functions including consciousness, perception, control of reactions to the environment, emotional responses, and judgement.
brain
The area of the brain between the spinal cord and cerebrum that contains the midbrain, pons, and medulla; controls functions that are necessary for life, such as breathing.
brainstem
Abnormal whooshing sounds indicating turbulent blood flow within a narrowed blood vessel, usually heard in the carotid arteries.
bruit
Fast-acting defenses for acid-base changes, providing almost immediate protection against changes in the hydrogen ion concentration of extracellular fluid.
buffer system
The portion of the conduction system of the heart located in the upper portion of the interventricular septum that conducts an electrical impulse from the atrioventricular function to the right and left bundle branches.
bundle of His
A small, padlike sac or cavity filled with a small amount of synovial fluid that helps reduce the amount of friction between a tendon and a bone or between a tendon and a ligament, usually located near a joint.
bursa
The heel bone; the largest of the tarsal bones.
calcaneus
The amount of heat needed to raise the temperature of a gram of after by 33 degrees Fahrenheit (1 degree Celsius); the amount of energy that can be obtained from the nutrients you eat; also called a kilocalorie.
calorie
Substances (including sugars and starches) that provide much of the energy required by the body’s cells, as well as helping to build cell structures.
carbohydrates
The repetitive pumping process that begins with the onset of cardiac muscle contraction and ends just before the beginning of the next contraction; each one consists of ventricular contraction (systole) and relaxation (diastole).
cardiac cycle
The point of bifurcation of the right and left primary (mainstem) bronchi.
carina
The eight small bones of the wrist.
carpal bones
Those connected by hyaline cartilage, or fibrocartilage, such as the joints that separate the vertebrae.
cartilaginous joints
The breakdown of larger molecules into smaller ones.
catabolism
Clouding of the lens of the eye or its surrounding transparent membrane.
cataract
Amine substances such as dopamine, epinephrine, and norepinephrine that function as neurotransmitters, hormones, or both.
catecholamines
The cell wall; a selectively permeable layer of cells that surround intracellular contents and control movement of substances into and out of the cell; also called the cytoplasmic membrane or plasma membrane.
cell membrane
A biochemical process resulting in the production of energy in the form of adenosine triphosphate.
cellular respiration
The brain and spinal cord.
central nervous system (CNS)
Area of the brain involved in fine and gross muscle coordination; responsible for interpretation of actual movement and correction of any movements that interfere with coordination and the body’s position.
cerebellum
The outer covering of gray matter that covers the cerebral hemispheres; regulates voluntary skeletal movement and plays an important role in one’s level of awareness.
cerebral cortex
Pressure inside the cerebral arteries and an indicator of brain perfusion; calculated by subtracting intracranial pressure from mean arterial pressure.
cerebral perfusion pressure (CPP)
Fluid produced in the ventricles of the brain that flows in the subarachnoid space and bathes the meninges.
cerebrospinal fluid (CSF)
The largest part of the brain; made up of several lobes that control movement, hearing, balance, speech, visual perception, emotions, and personality; divided into right and left hemispheres; also called gray matter.
cerebrum
The interior of the cervix.
cervical canal
The lower one-third or neck of the uterus.
cervix
Sense organs that monitor the levels of oxygen and carbon dioxide and the pH of cerebrospinal fluid and blood and provide feedback to the respiratory centers to modify the heart rate and depth of.breathing based on the body’s needs at any given time.
chemoreceptors
Having the characteristics of the parasympathetic division of the autonomic nervous system; also refers to other structures or functions that are related to acetylcholine.
cholinergic
Thin bands of fibrous tissue that attach to the atrioventricular valves in the heart and prevent them from inverting.
chordae tendineae
The vascular, pigmented middle layer of the eye wall.
choroid
Group of specialized cells in the ventricles of the brain; filters blood through cerebral capillaries to create cerebrospinal fluid.
choroid plexus
Structures formed from condensed fibers and protein of deoxyribonucleic acid; they are threadlike, and are contained within the nucleus of the cells.
chromosomes
Related to the effect of the rate of contraction of the heart.
chronotropic effect
The structure associated with the choroid layer of the eye that secretes aqueous humor and contains the ciliary muscle.
ciliary body
The complex arrangement of connected tubes, including the arteries, arterioles, capillaries, venules , and veins, that moves blood, oxygen, nutrients, carbon dioxide, and cellular waste throughout the body.
circulatory system
One of two branches of the left main coronary artery.
circumflex coronary artery
A sequence of enzymatic reactions involving the metabolism of carbon chains of glucose, fatty acids, and amino acids to yield carbon dioxide, water, and high-energy phosphate bonds; also known as he Krebs cycle or tricarboxylic acid cycle.
citric acid cycle
A set of interactions that lead to the formation of a fibrin clot; also called the coagulation cascade.
clotting cascade
The portion of the inner ear that has hearing receptors.
cochlea
A substance that can be broken down into the two or more elements contained within it.
compound
The property that allows a cardiac cell to receive an electrical impulse and pass it on to an adjoining cardiac cell.
conductivity
One of two photoreceptors of the retina that can distinguish colors, but requires a greater amount of light to activate and create an image.
cones
The membranous covering on the anterior surface of the eye that also lines the eyelids.
conjunctiva
Inflammation of the conjunctiva.
conjunctivititis
Tissues that bind, support, protect, frame, and fill body structures; they also store fat, produce blood cells, repair tissues, and protect against infection.
connective tissues
The ability of myocardial cells to shorten in response to an impulse, which results in contraction.
contractility
The transparent tissue layer in front of the pupil and iris of the eye.
cornea
Venous drain for the coronary circulation into the right atrium.
coronary sinus
A deep bridge of nerve fibers connecting the brain hemispheres.
corpus callosum
Any of several steroids secreted by the adrenal gland.
corticosteroids
A glucocorticoid of the middle adrenal cortex that influences protein and fat metabolism and stimulates glucose to be synthesized from noncarbohydrates.
cortisol
The 12 pairs of nerves that arise from the base of the brain.
cranial nerves
The bones that encase and protect the brain, including the parietal, temporal, frontal, occipital, sphenoid, and ethmoid bones; the roof of the skull (cranium).
cranial vault
The area of the head above the ears and eyes; the part of the skull that houses the brain.
cranium
A horizontal bone perforated with numerous openings for the passage of the olfactory nerve filaments from the nasal cavity.
cribiform plate
A firm ridge of cartilage that forms the lower part of the larynx; the first ring of the trachea and the only upper airway structure that forms a complete ring; also called the cricoid ring.
cricoid cartilage
A thin sheet of fascia located between the thyroid and cricoid cartilage that is relatively a vascular an contains few nerves; the site for emergency access to the airway.
cricothyroid membrane
The gel-like material that fills out a cell; it makes up most of the volume of the cell, and suspends the organelles of the cell.
cytoplasm
A dense layer of fibrous tissue below the subcutaneous tissue; composed of tough bands of tissue that surround muscles and other internal structures.
deep fascia
Branchlike projections of nerve cells that receive impulses or sensory information from nearby cells and conduct impulses toward the nerve cell body.
dendrites
Specialized structure within the cell that carries genetic material for reproduction.
deoxyribonucleic acid (DNA)
In response to an action potential, the rapid movement of electrolytes across a cell membrane that changes overall charge of the cell. This rapid shifting of electrolytes and cellular charges is the main catalyst for muscle contractions and neural transmissions.
depolarization
The area of the skin supplied by a specific sensory spinal nerve.
dermatome
The portion of the aorta that extends through the thorax and abdomen into the pelvis.
descending aorta
A process whereby leukocytes move through the wall of a capillary and out to the tissues where they are needed most.
diapedesis
Large skeletal muscle that plays a major role in breathing and separates the chest cavity from the abdominal cavity.
diaphragm
The shaft of a long bone.
diaphysis
Phase of the cardiac cycle in which the atria and ventricles relax between contractions and blood enters these chambers.
diastole
Portion of the brain between the brainstem and cerebrum; contains the epithalamus, the thalamus, the hypothalamus, and the subthalamus.
diencephalon
The process of specialization of a cell.
differentiation
The process of particles moving from an area of higher concentration to an area of lower concentration along a concentration gradient until equilibrium is achieved.
diffusion
The chemical breakdown of food material into smaller fragments that can be absorbed into the circulatory system.
digestion
Cells that carry two of each of the 23 chromosomes—-one from the father and one from the mother.
diploid cells
A portion of the medulla oblongota that functions as an respiratory integration center; it receives input from several sources including the pontine respiratory group, sensory input through the glossopharyngealand vagus nerves, central chemoreceptors in the medulla and peripheral chemoreceptors.
dorsal respiratory group (DRG)
The outermost of the three meninges that enclose the brain and spinal cord; it is the toughest meningeal layer.
dura mater
Salt or acid substances that become ionic conductors when dissolved in a solvent (such as water); chemicals dissolved in the blood.
elecrtolytes
The thin membrane lining the inside of the heart.
endocardium
Glands that have no ducts and secrete directly into tissue fluid or blood.
endocrine glands
The complex message and control system that integrates many body functions, including the release of hormones.
endocrine system
The fluid containing nerve receptors that resides inside the membranous labyrinth. Sound waves converted into pressure waves are transmitted through this fluid to the auditory nerves.
endolymph
A subdivision of the autonomic nervous system that controls the digestive system.
enteric nervous system (ENS)
Substances designed to speed up the rate of specific biochemical reactions.
enzymes
A leukocyte that may play a role following infection in various areas in the body.
eosinophil
The layer of the serous pericardium that lies closely against the heart; also called the visceral pericardium.
epicardium
A thin, flaplike structure that allows air to pass into the trachea but prevents food and liquid from entering.
epiglottis
A hormone produced by the adrenal medulla that has a vital role in the function of the sympathetic division of the autonomic nervous system; medicates the fight-or-flight response; also called adrenaline.
epinephrine
The growth plate of a long bone; a major site of bone development during childhood; also called the physis.
epiphyseal plate
Body tissues that cover organs, form the inner lining of cavities, and line hollow organs.
epithelial tissues
A hormone released from the ovaries that stimulates the uterine lining during the menstrual cycle.
estrogen
A branch of the internal auditory canal that connects the middle ear to the oropharynx.
eustachian tube
The ability of cardiac muscle cells to respond to an electrical, chemical, or mechanical stimulus.
excitability
The passive part of the breathing process in which the diaphragm and the intercostal muscles relax, forcing air out of the lungs.
exhalation
Glands that secrete chemicals into ducts that open onto a surface for elimination.
exocrine glands
The amount of air that can be exhaled following a normal exhalation; average volume is about 1,200 mL.
expiratory reserve volume
Fluid outside of the cell, in which most of the body’s supply of sodium is contained; accounts for 15% to 20% of body weight.
extracellular fluid (ECF)
Referring to the eye; six muscles that attach to the exterior of the globe an are controlled by the cranial nerves.
extrinsic muscles
A sheet or band of tough fibrous connective tissue that covers, supports, and separates muscles, and which also cover arteries, veins, tendons, and ligaments.
fascia
A white, insoluble protein formed by the action of thrombin on fibrinogen during the blood clotting process; forms the matrix of a blood clot.
fibrin
A plasma protein protein that is important for blood clotting.
fibrinogen
Joints that lie between bones that closely contact each other, joined by thin, dense connective tissue.
fibrous joints
The movement of fluid from intravascular fluid under high pressure to interstitial fluid, which is generally under lower pressure.
filtration
The process of maintaining homeostasis through equal intake (water taken into the body) and output (water excreted from the body) of fluids.
fluid balance
The soft spots in the skull of a newborn and infant where the sutures of the skull of a newborn and infant where the sutures of the skull have not yet grown together.
fontanelles
The percentage of oxygen in inhaled air.
fraction of inspired oxygen (FiO2)
A normal neural reflex elicited by touching the soft palate or posterior pharynx; the responses are symmetric elevation of the palate, retraction of the tongue, and contraction of the pharyngeal muscles.
gag reflex
Sensations monitored throughout the body by receptors scattered throughout many different tissues.
general senses
The arrangement of a person’s genes and their characteristics is based on the combination of alleles, for one gene or many.
genotype
A disease of the eye caused by an increase in intraocular pressure; when severe enough, this may damage the optic nerve and potentially cause permanent loss of vision.
glaucoma
Antibodies made by the liver or lymphatic tissues that make up around 36% of the plasma proteins.
globulins
The true vocal cords and the opening between them.
glottis
A process that stimulates both the liver and the kidneys to produce glucose from non carbohydrate molecules.
gluconogenesis
A long polymer from which glucose is converted in the liver (animal starch).
glycogen
The breakdown of glycogen to glucose.
glycogenolysis
Process by which glucose and other sugars are broken down to yield lactic acid (anaerobic glycolysis) or pyrrhic acid (aerobic glycolysis). The breakdown releases energy in the form of adenosine triphosphate.
glycolysis
Cells that carry genetic instructions via 23 individual chromosomes.
haploid cells
The anterior portion of the palate that is supported by bone (primarily the maxillary bone).
hard palate
A measure of the relative percentage of blood cells (mainly erythrocytes) in a given volume of whole blood.
hematocrit
Th blood components and the organs involved in their development and production.
hematopoietic system
An iron-containing pigment found in red blood cells that carries oxygen to the cells from the lungs and carbon dioxide away from the cells to the lungs.
hemoglobin
The stoppage of bleeding; involves the steps of blood vessel spasm, platelet plug formation, and blood clotting.
hemostasis
A law of gas that states the amount of a gas in a solution varies directly with the partial pressure of a gas over a solution.
Henry’s law
A specialized part of the venous system that carries blood from the digestive tract to the liver and then to the inferior vena cava.
hepatic portal system
A protective mechanism that terminates inhalation, thus preventing over expansion of the lungs.
Hering-Breuer reflex
A substance found in large amounts in basophils that increases tissue inflammation.
histamine
A tendency to constancy or stability in the body’s internal environment; processes that balance the supply and demand of the body’s needs.
homeostasis
A chromosome of the same numbered pair from the opposite parent.
homologous chromosome
A substance that is produced in one tissue or organ and is released into the blood and carried to other (target) organs, where it acts to produce a specific response.
hormone
The pressure of water against the walls of its container.
hydrostatic pressure
A small, horseshoe-shaped bone to which the jaw, tongue, epiglottis, and thyroid cartilage attach.
hyoid bone
Farsighted; the ability to see distant objects with difficulty focusing on objects close.
hyperopia
Concentration of solute is higher compared with another solution.
hypertonic
An area of the diencephalon that is the primary link between the the endocrine system and the nervous system; responsible for control of many body functions, including heart rate, digestion, sexual development, temperature regulation, emotion, hunger, thirst, and regulation of the sleep cycle.
hypothalamus
Concentration of solute is lower compared with another solution.
hypotonic
A situation in which a person’s stimulus to breather comes from a decrease in PaO2 rather than the normal stimulus, and increase in PaCO2.
hypoxia drive
The body’s ability to protect itself from acquiring a disease.
immunity
The active process of moving air into the lungs; also called inspiration; also a route of medication delivery.
inhalation
The effect on the contractility of muscle tissue, especially cardiac muscle.
inotropic effect
A moveable part of the body to which a skeletal muscle is fastened at a moveable joint; its action opposes that of an origin.
insertion
The additional amount of air that can be inhaled after the normal tidal volume has been reached.
inspiratory reserve volume
The largest organ system in the body, consisting of the skin and accessory structures (eg, hair, nails, glands).
integumentary system
The fluid located outside of the blood vessels in the spaces between the body’s cells.
interstitial fluid
The space in between the cells.
interstitial space
Fluid within cells in which most of the body’s supply of potassium is contained; accounts for 40% to 45% of body weight.
intracellular fluid (ICF)
Fluid outside cells but inside the circulatory system; the majority of it is plasma, which is the fluid component of blood.
intravascular fluid
A chemical bond where oppositely charge ions attract each other.
ionic bond
Atoms that have become positively or negatively charged, either by giving up or acquiring an electron.
ions
Groups of cells located in the pancreas that produce insulin, glucagon, somatostatin, and pancreatic polypeptide.
islets of Langerhans
A solution in which there is an equal concentration of solutes and water on either side of a semipermeable membrane. In this case, water does not shift, and no change in cell shape occurs.
isotonic solution
A saclike envelope that encloses the cavity of a synovial joint.
joint capsule
The amount of heat needed to raise the temperature of a gram of water by 33 degrees Fahrenheit (1 degree Celsius); nutrients you eat; also known as a calorie
kilocalorie
Two prominent, rounded folds of skin lateral to the labia minora of the female external genitalia.
labia majora
A pair of skin folds in the female external genitalia that border the vestibule.
labia minora
The glands that produce fluids to keep the eye moist; also called tear glands.
lacrimal glands
A metabolic end product of the breakdown of glucose that accumulates when metabolism proceeds in the absence of oxygen.
lactic acid
A complete structure formed by the epiglottis, thyroid cartilage, cricoid cartilage, arytenoid cartilage, corniculate cartilage, and cuneiform cartilage; also called the voice box.
larynx
One of the two branches of the left main coronary artery that supplies blood to the left ventricle and other areas of the heart.
left anterior descending artery
The transparent disc within the eye that refracts light to focus image on the retina.
lens
Fats, fatlike substances (cholesterol and phospholipids), and oils that supply energy for body processes and building of certain structures.
lipids
A thin liquid formed from interstitial fluid that flows through the lymphatic vessels and lymph nodes and aids in immune response and debris removal.
lymph
Round or bean-shaped structures interspersed along the course of the lymph vessels, which filter the lymph and serve as a source of lymphocytes.
lymph nodes
Unidirectional, thin-walled vessels through which lymph circulates through the body; they travel close to the major veins.
lymph vessels
A network of capillaries, vessels, ducts, nodes, and organs that helps to maintain the fluid environment of the body by producing lymph and transporting it through the body.
lymphatic system
A type of white blood cell that has an important role in immunity.
lymphocytes
Large cells, usually derived from monocytes, that are specialized for phagocytosis; they kill pathogens, absorb foreign materials, and slow infections and infectious agents.
macrophages
A yellow depression in the retina where acute vision arises; also know as the macula lutea.
macula
Cells located in connective tissues to which antibodies, formed in response to allergens, attach, bursting the cells and releasing chemical mediators in response to an antigen-antibody reaction.
mast cells
The space between the lungs, in the center of the chest, that contains the heart, great vessels, part of the esophagus, lymphatic channels, trachea, primary bronchi, and paired vagus and phrenic nerves.
mediastinum
Inferior part of the brainstem that is continuous inferiorly with the spinal cord; serves as a conduction pathway for ascending and descending nerve tracts; responsible for maintenance of basic life functions, such as heart rate and breathing.
medulla oblongata
A type of cell division that occurs in the production of eggs and sperm.
meiosis
The pigment that gives skin its color.
melanin
The first menstrual cycle; the onset of menses.
menarche
A set of three tough membranes, the dura mater, arachnoid, and pia mater, that enclose the entire brain and spinal cord.
meninges
The period when a woman’s reproductive cycle ceases; also called the female climacteric.
menopause
Cyclical shedding of the endometrial lining.
menstruation
The five bones that form the palm and back of the hand.
metacarpals
The most superior portion of the brainstem; it works with the pons to route information from higher within the brain to the spinal cord and vice versa.
midbrain
An inorganic element essential for human metabolism.
mineral
The amount of air that moves in and out of the lungs per minute minus the dead space; also called minute ventilation.
minute volume
The division of chromosomes in a cell nucleus.
mitosis
The atrioventricular valve in the heart that separates the left atrium from the left ventricle.
mitral valve
White blood cells that mature in the blood and then travel to the tissues, where they differentiate into macrophages; these function primarily as scavengers for the tissues.
monocytes
Nerve that carries information from the central nervous system to the muscles of the body.
motor nerve
Nerve cells that transmit instructions from the central nervous system to the end organs; also known as efferent neurons.
motor neurons
The lining of body cavities and passages that communicate directly or indirectly with the environment outside the body.
mucous membrane
The opaque, sticky secretion of the mucous membranes that lubricates the body openings.
mucus
An abnormal heart sound, heard as a “whooshing,” indicating turbulent blood flow within the heart.
murmur
Contractile tissue consisting of filaments of actin and myosin, which slide past each other, shortening cells.
muscle tissue
The bones and voluntary muscle of the body.
musculoskeletal
The middle and thickest layer of the heart; it contains the cardiac muscle fibers that cause contraction of the heart, as well as the conduction system and blood supply.
myocardium
A pigment synthesized in the muscles to give skeletal muscles their red-brown color.
myoglobin
Nearsighted; the ability to see objects close with difficulty seeing objects far away.
myopia
A contractile protein found in the thick filaments of skeletal muscle cells.
myosin
The part of the pharynx that lies above the level of the palate.
nasopharynx
The concept that once the desired effect of a process has been achieved, further action is inhibited until it is needed again; also called feedback inhibition.
negative feedback
Drawing of air into the lungs; airflow from a region of higher pressure (outside the body) to a region of lower pressure (the lungs); occurs during normal breathing.
negative pressure ventilation
A mas of tissue produced by abnormal cell growth and division that may be malignant (cancerous) or benign.
neoplasm
The functional (urine-producing) units of the kidneys.
nephrons
The system that controls virtually all activities of the body, both voluntary and involuntary.
nervous system
Composed of neurons and neuroglia.
nervous tissue
Supporting cells that provide a supporting skeleton for neural tissue, isolate and protect the cell membranes of neurons, regulate the composition of interstitial fluid, defend neural tissue from pathogens, and aid in the repair of injury.
neuroglia
The connection between a motor neuron and a muscle fiber.
neuromuscular junction
The basic nerve cells of the nervous system, containing a nucleus within a cell body and extending one or more processes; they exist in masses to form nervous tissue.
neurons
A chemical released from one nerve that crosses the synaptic cleft to reach a receptor.
neurotransmitter
One of the three types of granulocytes; they have multi-lobed nuclei that resemble a string of baseballs held together by a thin strand of thread; they destroy bacteria, antigen-antibody complexes, and foreign matter.
neutrophils
A naturally occurring catecholamine that functions as a neurotransmitter and adrenal hormone; it is synthesized by the adrenal medulla, the peripheral sympathetic nerves, and the central nervous system. It is also available as a drug sometimes used in the treatment of severe hypotension; produces vasoconstriction through its alpha-stimulator properties.
norepinephrine
Large organic molecules, or macromolecules, that carry genetic information of form structures within cells, and include deoxyribonucleic acid and ribonucleic acid.
nucleic acids
In the context of the cell, a cellular organelle that contains the genetic information; controls the function and structure of a cell. In the context of an atom, the central portion of an atom that contains protons and neutrons.
nucleus
Substances that provide nourishment for growth such as carbohydrates, lipids, proteins, vitamins, minerals, and water.
nutrients
A simple sugar composed of 2 to 10 monosaccharides.
oligosaccharide
The pressure of water to move, typically into the capillary, as the result of the presence of plasma proteins
oncotic pressure
Immature female sex cell produced in the ovary that may develop by meiosis into an ovum (egg).
oocyte
The process of egg cell formation, which begins at puberty.
oogenesis
Location where approximately half of the nerve fibers from each eye cross over to the opposite side of the brain.
optic chiasm
An eye socket of the skull.
orbit
The organ that is the primary receptor for sound, and is made up of thousands of individual cilia, each with their own associated nerve.
organ of Corti
Structures within cells that have specialized functions.
organelles
A relatively immovable part of the body where a skeletal muscle is fastened at a moveable joint; its action opposes that of an insertion.
origin
A tubular structure that extends vertically from the back of the mouth to the esophagus and trachea.
oropharynx
The movement of a solvent, such as water, from an area of low solute concentration to one of high concentration through a selectively permeable membrane to equalize concentration of a solute on both sides of the membrane.
osmosis
The pressure exerted by the concentration of the solutes in a given space the flow of solvent across a semipermeable membrane.
osmotic pressure
The formation of bone by osteoblasts.
ossification
Cells involved in the formation of bony tissue.
osteoblasts
Macrophages of the bone surface that dissolve the matrix and return minerals to the extracellular fluid.
osteoclasts
Mature bone cells.
osteocytes
A pair of fluid-filled sacs within the inner ear that are used by the central nervous system to collect information about movement and orientation in space.
otoliths
The opening between the stapes and inner ear.
oval window
Female glands that produces sex hormones and ova (eggs).
ovaries
Midcycle release of an ovum during the menstrual cycle.
ovulation
The process of loading oxygen molecules onto hemoglobin molecules in the bloodstream.
oxygenation
Hemoglobin that has oxygen molecules bound to it.
oxyhemoglobin
The roof of the nasal cavity; it separates the nasal cavity from the oral cavity.
palate
An organ with both endocrine and exocrine functions; it is a major source of digestive enzymes and produces the hormone insulin.
pancreas
Muscles attached to the chordae tendineae of the atrioventricular heart valves and the ventricular muscle of the heart.
papillary muscles
The sinuses, or hollowed sections of bone in the front of the head, which are lined with mucous membrane and drain into the nasal cavity; the frontal, ethmoid, sphenoid, and maxillary sinuses.
paranasal sinuses
Four glands that are embedded in the posterior portion of each lobe of the thyroid; they produce and secrete parathyroid hormone.
parathyroid glands
Hormone produced and secreted by the parathyroid glands; it maintains normal levels of calcium in the blood and normal neuromuscular function.
parathyroid hormone (PTH)
The lining of the pleural cavity attached tightly to the interior of the chest cage.
parietal pleura
The pressure exerted by an individual gas in a mixture.
partial pressure
The attachment of the lower extremities to the body, consisting of the sacrum and two pelvic bones.
pelvis
The cylindrical male sex organ; it conveys urine and semen through the urethra.
penis
Protein molecule consisting of amino acids held together by peptide bonds.
peptide
Becoming aware of or understanding something using the senses.
perception
The circulation of oxygenated blood within an organ or tissue in adequate amounts to meet the cell’s current needs.
perfusion
A thin, double-layered membrane made up of the fibrous pericardium and serous pericardium.
pericardium
Fluid within the bony labyrinth that surrounds and protects the membranous labyrinth while allowing transmission of pressure waves caused by sound.
perilymph
The part of the nervous system that consists of 31 pairs of spinal nerves and 12 pairs of cranial nerves that are responsible for communication between the central nervous system and the rest of the body. These may be sensory nerves, motor nerves, or connecting nerves.
peripheral nervous system (PNS)
The wavelike contraction of smooth muscle by which the ureters or other tubular organs propel their contents.
peristalsis
Double-layered serous membrane that lines the abdominal cavity and covers the organs located in the abdominopelvic cavity.
peritoneum
The measure of acidity or alkalinity of a solution.
pH
A form of endocytosis in which a cell surrounds a foreign particle and engulfs it.
phagocytosis
a sensation of pain in a part of the body that is no longer present.
phantom pain
The area between the nasal cavity and the larynx and posterior to the oral cavity; the throat.
pharynx
The appearance, health condition, or other characteristics associated with a particular genotype.
phenotype
A type of lipid molecule that comprises the cell membrane.
phospholipid
The study of the processes and functions of the living organism.
physiology
The innermost of the three meninges that enclose the brain and spinal cord; it rests directly on the brain and spinal cord.
pia mater
A gland in the brain that synthesizes and secretes melatonin, a hormone that affects patterns of sleep and wakefulness.
pineal gland
A formation of cartilage within the inner ear that protects the ear and collects into the ear canal, while allowing some perception of the direction from which the sound comes; also called the auricle.
pinna
A form of endocytosis in which the cell membrane sinks inward and ingests droplets of extracellular fluid.
pinocytosis
An endocrine gland responsible for directly or indirectly affecting all body functions; also called the hypophysis.
pituitary gland
A watery, yellow fluid that carries the blood cells and nutrients transports cellular waste material to the organs of excretion.
plasma
Cells that produce antibodies (immunoglobulins) to destroy antigens or antigen-containing particles; formed from divided and differentiated B cells.
plasma cells
A naturally occurring enzyme that dissolves the fibrin fibers in blood clots; usually present in the body in its inactive form, plasminiogen.
plasmin
Formed elements of the blood that function in blood clotting; also called thrombocytes.
platelets
The serous membranes covering the lungs and lining the thoracic cavity.
pleura
The potential space between the parietal pleura and the visceral pleura.
pleural space
A cluster of nerve roots that permits peripheral nerve roots to rejoin and function as a group.
plexus
When a cell is at rest, ions are actively transported into and out of the cell to create an electrochemical gradient across the cell membrane.
polarized
Formed from many amino acids bound into a chain. When this has more than 100 molecules, it is considered to be a protein. Certain protein molecules have more than one.
polypeptide
Complex carbohydrates that contain many simple joined sugar units, such as plant starch. Some, such as cellulose, cannot be broken down for nutrition in humans but play important roles in digestion.
polysaccharides
Area of the brainstem that contains the sleep and respiratory centers for the body, which along with the medulla, control breathing.
pons
A portion of the pons that communicates information to both the ventral and dorsal respiratory groups; it is thought to smooth the transition between each phase of the ventilatory cycle and alter breathing by making each breath shorter and shallower or longer and deeper, depending on the body’s needs.
pontine respiratory group (PRG)
Smooth muscle located at the entrances to the capillaries; responsive to local tissue needs.
precapillary sphincters
The volume of blood in the ventricle at the end of diastole; it is primarily a reflection of venous return (the blood that is returned to the heart).
preload
The increased difficulty in focusing on objects that occurs with aging.
presbyopia
A female hormone released from the ovaries that promotes changes in the uterus during the reproductive cycle, affects the mammary glands, and helps regulate gonadotropin secretion.
progesterone
The awareness of motion and position of a body part.
proprioception
Lipids made from arachidonic acid that usually act more locally than hormones, are very potent, stimulate hormone secretions, and help to regulate blood pressure.
prostaglandins
Created from amino acids, they include enzymes, plasma proteins, muscle components (actin and myosin), hormones, and antibodies.
proteins
A protein made in the liver and released into the blood where it is converted into thrombin during the process of blood clotting.
prothrombin
One of two arteries that carry deoxygenated blood from the right ventricle to the lungs.
pulmonary artery
The flow of blood from the right ventricle through the pulmonary arteries and all of their branches and capillaries in the lungs and back to the left atrium through the venules and pulmonary veins; also called the lesser circulation.
pulmonary circulation
The four veins that return oxygenated blood from the lungs to the left atrium of the heart.
pulmonary veins
The semilunar valve that regulates blood flow between the right ventricle and the pulmonary artery; also called the pulmonary semilunar valve.
pulmonic valve
The difference between the systolic and diastolic pressures.
pulse pressure
A system of fibers in the ventricles that conducts the excitation impulse from the bundle branches to the myocardium.
Purkinje fibers
Pain that feels as f it is originating from a body part other than the site being stimulated.
referred pain
A sensory message that reaches the spinal cord and meets with a motor nerve to cause an action; the reflex action occurs without the message first having to reach the brain to voluntarily cause the action.
reflex arc
A series of transparent structures within the eye that redirect light as it passes through mediums of different densities.
refracting system
The initial blood-filtering component of the nephron.
renal corpuscle
The outer portion of each kidney; it forms renal columns and has tiny tubules associated with the nephrons.
renal cortex
The inner portion of each kidney; it is made of conical renal pyramids, and has striations.
renal medulla
A cone-shaped collecting area that connects the ureter and the kidney.
renal pelvis
The portion of the nephron containing the tubular fluid filtered through the glomerulus.
renal tubule
A hormone produced by cells in the juxtaglomerular apparatus when the blood pressure is low.
renin
The process by which ions are moved across the cell membrane to return to a polarized state.
repolarization
The system in males and females that controls the reproductive processes via organs and glands that create sex cells and transport them to areas where fertilization can occur.
reproductive system
The amount of air remaining in the lungs and airway passages that is unable to be expelled after a maximal forced exhalation.
residual volume
The exchange of gases between a living organism and its environment.
respiration
Where gas exchange takes place; oxygen is picked up in the bloodstream and carbon dioxide is eliminated through the lungs.
respiratory membrane
All the structures of the body that contribute to the process of breathing, consisting of the upper and lower airways and their component parts.
respiratory system
Group of specialized neurons in the brainstem; involved in sleep and wake cycles; maintains consciousness.
reticular activating system (RAS)
The inner layer of the eye wall, including the visual receptors.
retina
An antigen found on the red blood cells of most people; when a woman without this protein is impregnated by a man with this protein, the woman’s body can create antibodies against the protein and attack future pregnancies.
Rh factor
Blood vessel that provides oxygenated blood to the right side of the heart muscle.
right coronary artery
One of two photoreceptors of the retina sensitive to light, but does not discriminate colors, producing a picture that is somewhat less focused and essentially black and white.
rods
The point of attachment of the ilium to the sacrum.
sacroiliac joint
Two saddle-shaped articulating surfaces oriented at right angles to each other so that complementary surfaces articulate with each other, such as is the case with the thumb.
saddle joint
Neuroglial cells in the peripheral nervous system that form a myelin sheath around axons.
Schwann cells
The white, fibrous outer layer of the eyeball.
sclera
A pouch of skin and subcutaneous tissue hanging from the lower abdominal region, posterior to the penis.
scrotum
Glands that produce an oily substance called sebum, which discharges alone the shafts of the hairs.
sebaceous glands
The two valves, the aortic an pulmonic valves, that are shaped like half-moons and separate the heart from the aorta and pulmonary arteries.
semilunar (SL) valves
Property of the cell membrane that describes the ability to allow certain elements to pass through while not allowing others to do so.
semipermeable
The nerves that carry sensations of touch, taste, heat, cold, pain, and other modalities from the body to the central nervous system.
sensory nerves
Structures located in the dermis that initiate nerve impulses that can reach one’s conscious awareness.
sensory receptors
The X and Y chromosomes, which determine sex.
sex chromosomes
The normal site of the origin of electrical impulses; located high in the right atrium, it is the natural pacemaker of the heart.
sinoatrial (SA) node
Cavities formed by the cranial bones that trap contaminants from entering the respiratory tract and act as tributaries for fluid to and from the eustachian tubes and tear ducts.
sinuses
Voluntary muscle tissue attached to bones and composed of long, threadlike cells that have light and dark striations.
skeletal muscle tissue
A method of muscle contraction involving how sarcomeres shorten, with thick and thin filaments sliding past each other toward the center of the sarcomere from both ends.
sliding filament theory
The mechanism by which the cell brings in two potassium ions and releases three sodium ions.
sodium-potassium pump
The posterior portion of the palate that is made up of mucous membrane, muscular fibers, and mucous glands; it is so named because it has no bony support.
soft palate
The dissolved particles contained in a solvent.
solute
A mixture of a solvent and a solute.
solution
The fluid that dissolves a solute, or the substance in which a solute is dissolved or mixed.
solvent
The part of the nervous system that regulates activities over which there is voluntary control.
somatic nervous system
Pain caused by the activation of pain receptors in the body’s superficial tissues, such as the skin, bones, muscles, and joints; in contrast to visceral pain, this is generally more intense and more precisely localized.
somatic pain
The process by which sperm cell are formed.
spermatogenesis
Muscles arranged in circles that are able to decrease the diameter of tubes. Examples are found within the rectum, bladder, and blood vessels.
sphincters
31 pairs of nerves that originate from the spinal cord and exit the spine on either side between vertebrae; each has a sensory root and a motor root and is responsible for sending and receiving sensory and motor messages to and from the central nervous system from a portion of the body.
spinal nerves
Cells that retain the ability to divide repeatedly without specializing, and that allow for continual growth and renewal.
stem cells
Loss of perception of depth and overlapping or doubled images.
strabismus
The outermost of dead layer of the skin.
stratum corneum
The volume of blood pumped forward with each ventricular contraction.
stroke volume (SV)
The space located between the pia mater and the arachnoid membrane.
subarachnoid space
The indentation formed by the superior border of the manubrium and the clavicles, often used as a landmark for procedures such as subclavian vein access; also known as the jugular notch.
suprasternal notch
A liquid protein substance that coats the alveoli in the lungs, decreases alveolar surface tension, and keeps the alveoli expanded; a low level in a premature infant contributes to respiratory distress sydrome.
surfactant
Seams that occur only between the bones of the skull; they are a type of fibrous joint.
sutures
The glands that secrete sweat, located in the dermal layer of the skin.
sweat glands
A functional connection where neurons communicate with other cells.
synapse
The space between neurons; also called the synaptic gap.
synaptic cleft
Small sacs that contain neurotransmitters.
synaptic vesicles
The fluid secreted by synovial membranes that lubricates synovial joints.
synovial fluid
Complex joints that allow free movement of the component bones and are lubricated with synovial fluid.
synovial joints
The lining of a joint that secretes synovial fluid into the joint space.
synovial membrane
The resistance that blood must overcome to be able to move within the blood vessels; related to the amount of dilation or constriction in the blood vessel.
systemic vascular resistance
Lymphocytes that interact directly with antigens, producing the cellular immune response; they also stimulate the B lymphocytes to produce antibodies; also called T cells.
T lymphocytes
A horizontal projection of the dura that separates the cerebellum from the cerebrum.
tentorium
The most important male sex hormone (androgen).
testosterone
Structure of the diencephalon that is the sensory switchboard of the brain, through which almost all signals travel on their way in or out of the brain.
thalamus
The process by which the body maintains temperature through a combination of heat gain by metabolic processes and muscular movement and heat loss through breathing, evaporation, conduction, convection, and perspiration.
thermoregulation
One of two great lymph vessels; it empties into the superior vena cava.
thoracic duct
An enzyme that causes the conversion of fibrinogen to fibrin, which binds to a platelet plug, forming a final mature clot.
thrombin
A chemical that stimulates blood clotting.
thromboplastin
A lymphatic organ located in the thorax that is important in early immunity; it shrinks with age and is eventually replaced by other types of tissue.
thymus
A firm prominence of cartilage that forms the upper part of the larynx; the Adam’s apple.
thyroid cartilage
A large endocrine gland that is located at the base of the neck and produces and excretes hormones that influence growth, development, and metabolism.
thyroid gland
The amount of air moved in and out of the lungs in one relaxed breath; about 500 mL for an adult.
tidal volume
A group of cells that are similar in structure and function.
tissue
A noncontractile protein found in sarcomeres of cardiac and skeletal muscle.
titin
Total amount of fluid in the human body; accounts for about 60% of the weight of a healthy adult male; divided into various compartments.
total body water (TBW)
Fluid classified as extracellular but distinct because it is formed from the transport activities of cells. Examples include cerebrospinal fluid, bladder urine, the aqueous humor, and the synovial fluid of the joints.
transcellular fluid
The atrioventricular valve that separates the right atrium from the right ventricle.
tricuspid valve
An actin-binding protein that regulates muscle contraction and other actin-related mechanical functions of the body.
tropomysin
A regulatory protein in the actin filaments of skeletal and cardiac muscle that attaches to tropomyosin.
troponin
The process that moves substances from the tubular fluid into the blood, within the peritubular capillary.
tubular reabsorption
The process that moves substances from the blood in the peritubular capillary into the renal tubule.
tubular secretion
The outer layer of tissue of a blood vessel wall, composed of elastic and fibrous connective tissue.
tunica adventitia
The smooth, thin, inner lining of a blood vessel.
tunica intima
The middle and thickest layer of tissue of a blood vessel wall, composed of elastic tissue and smooth muscle cell that allow the vessel to expand or contract in response to changes in blood pressure and tissue demand.
tunica media
A small, hollow tube that carries urine from the kidneys to the bladder.
ureter
The canal that conveys urine from the bladder to outside the body.
urethra
A sac behind the pubic symphysis made of smooth muscle that collects and stores urine.
urinary bladder
The organs that control the discharge of certain waste materials filtered from the blood and excreted as urine.
urinary system
A muscular, inverted pear-shaped organ that lies situated between the urinary bladder and the rectum.
uterus
The mechanical process of moving air into and out of the lungs in two separate phases: inhalation (inspiration) and exhalation (expiration).
ventilation
An area of the medulla oblongata that can cause inspiration or expiration depending on which motor neurons are stimulated.
ventral respiratory group (VRG)
The structure into which the vagina opens posteriorly, and the female urethra opens into in the midline; also the central part of the labyrinth of the ear, behind the cochlea and in front of the semicircular canals.
vestibule
Deep pain caused by activation of pain receptors in internal areas of the body that are enclosed within a cavity, such as the chest, abdomen, or pelvis.
visceral pain
Lining of the pleura cavity that adheres tightly to the surface of the lung.
visceral pleura
The amount of air moved in and out of the lungs with maximum inspiration and exhalation.
vital capacity
Organic compounds required for normal metabolism.
vitamins
A jellylike fluid filling the posterior eye cavity that helps the globe maintain its shape without distorting light.
vitreous humor
Bundles of myelinated nerves.
white matter