EMT Full Vocabulary

abdomen

The body cavity that contains the major organs of digestion and excretion. It is located below the diaphragm and above the pelvis.

acetabulum

The depression on the lateral pelvis where its three component bones join, in which the femoral head fits snugly.

acid

A substance that increases the concentration of hydrogen ions in a solution.

acidosis

A pathologic condition that results from the accumulation of acids in the body; an increase in extracellular H+ ions; a blood pH of less than 7.35.

acromioclavicular (AC) separation

One or more torn ligaments in the acromioclavicular joint, resulting in a separated shoulder.

acromion process

The tip of the shoulder and the site of attachment for the clavicle and various shoulder muscles.

active transport

A method used to move compounds across a cell membrane to create or maintain an imbalance of charges.

adenosine triphosphate (ATP)

The nucleotide involved in energy metabolism; used to store energy.

adrenal cortex

The outer layer of the adrenal gland; it produces hormones that are important in regulating the water and salt balance of the body.

adrenal glands

Endocrine glands located on top of the kidneys that release adrenaline when stimulated by the sympathetic nervous system.

adrenaline

Hormone produced by the adrenal glands that mediates the 'fight-or-flight' response of the sympathetic nervous system; also called epinephrine.

adrenocorticotropic hormone (ACTH)

Hormone that targets the adrenal cortex to secrete cortisol (a glucocorticoid).

aerobic metabolism

The metabolism that takes place in the presence of oxygen.

afterload

The pressure in the aorta against which the left ventricle must pump blood; increasing this pressure can decrease cardiac output.

agonist

A substance that mimics the actions of a specific neurotransmitter or hormone by binding to the specific receptor of the naturally occurring substance.

agranulocytes

Leukocytes that lack granules.

alkalosis

A pathologic condition resulting from the accumulation of bases in the body; a decrease in extracellular H+ ions; a blood pH greater than 7.45.

alpha cells

Cells located in the islets of Langerhans that secrete glucagon.

alpha effects

Stimulation of alpha receptors that results in vasoconstriction.

alveolar ducts

Ducts formed from division of the respiratory bronchioles in the lower airway; each duct ends in clusters known as alveoli.

alveoli

The air sacs of the lungs in which the exchange of oxygen and carbon dioxide takes place.

anaerobic metabolism

The metabolism that takes place in the absence of oxygen; the principal product is lactic acid.

anatomy

The study of the structure of an organism and its parts.

antagonist

A substance that counteracts the action of something else; a drug of this type has an affinity for a cell receptor and, when it binds to that receptor, the cell is prevented from responding.

antibody

A protein secreted by certain immune cells that bind antigens to make them more visible to the immune system; an immunoglobulin.

antigen

An agent that, when taken into the body, stimulates the formation of specific protective proteins called antibodies.

aorta

The main artery that receives blood from the left ventricle and delivers it to all the other arteries that carry blood to the tissues of the body.

aortic arch

One of the three described portions of the aorta; the section of the aorta between the ascending and descending portions that gives rise to the right brachiocephalic (innominate), left common carotid, and left subclavian arteries.

aortic valve

The one-way, semilunar valve that lies between the left ventricle and the aorta; keeps blood from flowing back into the left ventricle after the left ventricle ejects its blood into the aorta and is one of four heart valves.

appendicular skeleton

The portion of the skeletal system that comprises the arms, legs, pelvis, and shoulder girdle.

appendix

A small tubular structure that is attached to the lower border of the cecum in the lower right quadrant of the abdomen.

arachnoid

The middle membrane of the three meninges that enclose the brain and spinal cord.

areolar glands

The glands that produce secretions that protect the nipple and areola during nursing.

arteries

Vessels of the circulatory system that carry oxygenated blood away from the heart.

arterioles

The smallest branches of arteries leading to the vast network of capillaries.

ascending aorta

The first of three portions of the aorta; originates from the left ventricle and gives rise to two branches, the right and left main coronary arteries.

atlanto-occipital joint

The location where the atlas articulates with the occipital condyles.

atlas

The first cervical vertebra (C1), which provides support for the head.

atrioventricular (AV) node

The site located in the right atrium adjacent to the septum that is responsible for transiently slowing electrical conduction.

atrioventricular valves

The two valves through which blood flows from the atria to the ventricles.

atrium

One of two (right and left) upper chambers of the heart.

atrophy

A decrease in cell size as a result of a loss of subcellular components.

auditory ossicles

The bones that function in hearing and are located deep within cavities of the temporal bone.

autonomic nervous system

The part of the nervous system that regulates functions that are not controlled consciously, but rather involuntarily, such as heart rate, blood pressure, digestion, and sweating.

axial skeleton

The part of the skeleton comprising the skull, spinal column, and rib cage.

axillary vein

The vein that is formed from the combination of the basilic and cephalic veins; it drains into the subclavian vein.

axis

The second cervical vertebra (C2); the point that allows the head to turn.

ball-and-socket joint

A joint that allows internal and external rotation, as well as bending.

baroreceptors

Receptors in the blood vessels, kidneys, brain, and heart that respond to changes in pressure in the heart or main arteries to help maintain homeostasis.

base

A substance that decreases the concentration of hydrogen ions.

basilic vein

One of the two major veins of the arm; it combines with the cephalic vein to form the axillary vein.

basophils

White blood cells that work to produce chemical mediators during an immune response.

beta cells

Cells located in the islets of Langerhans that secrete insulin.

beta effects

Stimulation of beta receptors that results in inotropic, dromotropic, and chronotropic states.

biceps

The large muscle that covers the front of the humerus.

bile ducts

The ducts that convey bile between the liver and the intestine.

bilirubin

A waste product of red blood cell destruction that undergoes further metabolism in the liver.

blood

The fluid that is pumped by the heart through the arteries, veins, and capillaries and consists of plasma and formed elements or cells, such as red blood cells, white blood cells, and platelets.

blood pressure

The pressure that the blood exerts against the walls of the arteries as it passes through them.

bone marrow

A substance that manufactures most red blood cells.

brachial artery

The major vessel in the upper extremity that supplies blood to the arm.

brain

The controlling organ of the body and center of consciousness; functions include perception, control of reactions to the environment, emotional responses, and judgment.

brainstem

The area of the brain between the spinal cord and cerebrum, surrounded by the cerebellum; controls functions that are necessary for life, such as respiration and cardiac system functions.

bronchioles

Fine subdivisions of the bronchi made of smooth muscle that give rise to the alveolar ducts.

bronchospasm

Constriction of the airway passages of the lungs that accompanies muscle spasms.

bruit

An abnormal "whooshing" sound indicating turbulent blood flow within a blood vessel.

buffer

A substance or group of substances that controls the hydrogen levels in a solution.

buffer system

Fast-acting defenses for acid-base changes, providing almost immediate protection against changes in the hydrogen ion concentration of extracellular fluid.

bundle of His

Part of the conduction system of the heart; a continuation of the atrioventricular node.

bursa

A small fluid-filled sac located between a tendon and a bone that cushions and protects the joint.

calcitonin

A hormone produced by the parafollicular cells of the thyroid gland that is important in the regulation of calcium levels in the body.

cancellous bone

A type of bone that consists of a lacy network of bony rods called trabeculae.

capillaries

Microscopic, thin-walled blood vessels between the arterioles and venules through which oxygen, carbon dioxide, nutrients, and waste products are exchanged between body tissues and the blood.

cardiac cycle

The repetitive pumping process that begins with the onset of cardiac muscle contraction and ends just before the beginning of the next contraction.

cardiac muscle

The heart muscle.

cardiac output

The amount of blood pumped by the heart per minute; calculated by multiplying the stroke volume by the pulse rate per minute.

carotid artery

The major artery that supplies blood to the head and brain.

carpometacarpal joint

The joint between the wrist and the metacarpal bones; the thumb joint.

cartilage

The support structure of the skeletal system that provides cushioning between bones; also forms the nasal septum and portions of the outer ear.

catecholamines

Hormones produced by the adrenal medulla (epinephrine and norepinephrine) that assist the body in coping with physical and emotional stress by increasing the heart and respiratory rates and the blood pressure.

cecum

The first part of the large intestine, into which the ileum opens.

cell membrane

The cell wall; the cell membrane is selectively permeable.

cellular respiration

A biochemical process resulting in the production of energy in the form of adenosine triphosphate.

central nervous system (CNS)

The brain and spinal cord.

central vision

The visualization of objects directly in front of you.

cerebellum

One of the three major subdivisions of the brain, sometimes called the athlete's brain; coordinates the various activities of the brain, particularly fine body movements.

cerebrospinal fluid (CSF)

Fluid produced in the ventricles of the brain that flows in the subarachnoid space and bathes the meninges.

cerebrum

The largest part of the three subdivisions of the brain, sometimes called the gray matter; made up of several lobes that control movement, hearing, balance, speech, visual perception, emotions, and personality.

cervical spine

The portion of the spinal column consisting of the first seven vertebrae that lie in the neck.

cervix

The lower third, or neck, of the uterus.

chemoreceptors

Receptors in the blood vessels, kidneys, brain, and heart that respond to changes in chemical composition of the blood to help maintain homeostasis.

chordae tendineae

Thin bands of fibrous tissue that attach to the valves in the heart and prevent them from inverting, preventing regurgitation of blood through the valves from the ventricles to the atria.

choroid plexus

Specialized cells within hollow areas in the ventricles of the brain that produce cerebrospinal fluid.

chromosomes

Structures formed from condensed fibers and protein of deoxyribonucleic acid; they are threadlike and are contained within the nucleus of the cells.

chronic obstructive pulmonary disease (COPD)

A slow, progressive, degenerative, irreversible disease of the airway that causes destructive changes in the alveoli and bronchioles in the lungs.

chronotropic state

Related to the control of the heart's rate of contraction.

chyme

The name of the substance that leaves the stomach; a combination of eaten foods with added stomach acids.

circulatory system

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.

circumflex coronary arteries

One of the two branches of the left main coronary artery.

clavicle

The collarbone; it is lateral to the sternum and anterior to the scapula.