any disease-producing agent (especially a virus or bacterium or other microorganism)
any surface protein that may elicit an immune response or recognition
the organic process by which food is converted into substances that can be absorbed into the body
proteins that speed up chemical reactions in the body
enzyme found in saliva and pancreatic juice that breaks the chemical bonds in starches
enzyme that speeds up the breakdown of proteins into amino acids produced by the stomach, small intestine, and pancreas.
an enzyme secreted in the digestive tract that catalyzes the breakdown of fats into individual fatty acids that can be absorbed into the bloodstream
An organ of the digestive system that stores food and performs early steps of digestion.
organ that completes the chemical digestion of food and absorbs the nutrients
the last section of the digestive system, where water is absorbed from food and the remaining material is eliminated from the body
the process of absorbing nutrients into the body after digestion
the process where cells absorb nutrients and use them for what the body needs
fingerlike projection of the inner surface of the small intestine that functions in absorbing nutrients
multi-chambered, muscular organ that pumps blood throughout the body
the two arteries that supply oxygen-rich blood to the heart muscle
Describes muscle tissue (heart muscle) that generates its own contractions (w/o neuron impulse)
a specialized bit of heart tissue that controls the heartbeat
any bundle of fibers belonging to the nervous system that transmits sensations and messages between the brain and other parts of the body
part of the brain nearest the spinal cord (base of brainstem) which controls breathing, heart rate and blood pressure, the inner part of an organ or structure in plant or animal
adrenaline; affect sympathetic nervous system in stress response
blood vessels that carry oxygenated-blood away from the heart
the smallest blood vessels which connect the smallest arteries with the smallest veins. Nourishment and fluid noramlly trapped in thick walled arteries and veins can easily pass through the delicate walls of the capillaries
blood vessels that carry deoxygenated-blood back to the heart
liquid portion of blood made up of water, dissolved salts, proteins, and other substances
A red blood cell; they are filled with hemoglobin, and the function of the erythrocytes is to carry oxygen in the blood.
white blood cell that protects the body from invasion of harmful substances (i.e. infection)
a blood cell fragment that plays an important part in forming blood clots
chemicals that inhibit the growth of or kill other microorganisms
a nonliving, infectious particle composed of a nucleic acid and a protein coat; it can invade and destroy a cell
Prokaryotic, one-celled organisms. Some transmit diseases. Most act as decomposers and get the nutrients they need by breaking down complex organic compounds in the tissues of living or dead organisms into simpler inorganic nutrient compounds.
the process by which cells surround and digest certain particles
Protein that is produced by lymphocytes and that attaches to a specific antigen that aid in destroying infectious diseases
the virus that causes acquired immune deficiency syndrome (AIDS); it replicates and kills helper T-cells
a syndrome caused by the human immunodeficiency virus (HIV) that renders immune cells ineffective, permitting opportunistic infections, malignancies, and neurologic diseases to develop; transmitted sexually or through contaminated blood
the bodily process of inhalation and exhalation; the process of inhaling oxygen and exhaling carbon dioxide
breathing, transport of gases, and exchange of gases with tissue cells; Provides O2 for cellular respiration and removes its waste product, CO2
tiny sacs of lung tissue specialized for the movement of gases between air and blood
The windpipe; a passage through which air moves in the respiratory system.
two spongy organs, located in the thoracic cavity enclosed by the diaphragm and rib cage, responsible for respiration
two short branches located at the lower end of the trachea that carry air into the lungs.
progressively smaller tubular branches of the airways
Large, flat muscle at the bottom of the chest cavity that helps with breathing
Central Nervous System
the brain and spinal cord; the control center of the body
Peripheral Nervous System
the sensory and motor neurons that connect the central nervous system to the rest of the body
the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body
the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands
a layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next
nodes of ranvier
spaces between segments of myelin on the axons of neurons
the highly-excitable region of muscle fiber plasma membrane responsible for initiation of action potentials across the muscle's surface
the electrical discharge that travels along a nerve fiber
an interneuron which connects afferent neurons and efferent neurons in neural pathways
this carries information from the brain to the muscles; also called "efferent"
the potential difference between the two sides of the membrane of a nerve cell when the cell is not conducting an impulse
a neural impulse; a brief electrical charge that travels down an axon. the action potential is generated by the movement of positively charged atoms in and out of channels in the axon's membrane
collection of glands that secrete hormones into the blood which regulate growth, development, and homeostasis
metabolic equilibrium actively maintained by several complex biological mechanisms that operate via the autonomic nervous system to offset disrupting changes
A primary mechanism of homeostasis, whereby a change in a physiological variable that is being monitored triggers a response that counteracts the initial fluctuation.
A condition of abnormal use of glucose, usually caused by too little insulin or lack of response to insulin.