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Srry if there are repeats! :D


basic unit of functional structure in all organisms

cell membrane

surrounds the cell; controls what enters and exits the cell through semi-permeability


contains genetic information of the cell

golgi bodies

organelles that package materials to be transported in and out of the cell


involved in cell reproduction; not found in plant cells


contains enymes that break down materials in the cell


organelle which is the site of protein synthesis


stores wastes, as well as carbohydrates, water, salt, etc.

rough endoplasmic reticulum

functions in transport; called "rough" due to the presence of ribosomes on its surface

smooth endoplasmic reticulum

involved in synthesis of lipids


liquid within cell that contains all of the cell's organelles and serves as the cell's circulatory system


site of cellular respiration

cell wall

stiff protective surrounding to the cell made of cellulose; only found in plant cells


the maintainance of internal stability


excretion of waste products from sweat glands

nervous system

the sensory and control apparatus consisting of a network of nerve cells


the electrical discharge that travels along a nerve fiber


an organ having nerve endings that respond to stimulation


an organ (a gland or muscle) that becomes active in response to nerve impulses


a change in an organism's surroundings that causes a receptor to start impulses in a nerve pathway


a bodily process occurring due to the effect of some foregoing stimulus or agent


a cell that is specialized to conduct nerve impulses


the cell body of a neuron; contains nucleus


short fiber that conducts toward the cell body of the neuron


long nerve fiber that conducts away from the cell body of the neuron

myelin sheath

a layer of myelin encasing (and insulating) the axons of medullated nerve fibers

terminal branches

branched end of axon that contains neurotransmitters


the junction between two neurons (axon-to-dendrite) or between a neuron and a muscle


chemical used by a neuron to transmit an impulse across a synapse to another cell


anterior portion of the brain consisting of two hemispheres, involved in senses and the thought process


the "little brain" attached to the rear of the brainstem; it helps coordinate voluntary movement and balance


lower or hindmost part of the brain which is in control of most involuntary behaviors, including breathing rate and heart rate

spinal cord

a major part of the central nervous system which conducts sensory and motor nerve impulses to and from the brain


an automatic instinctive unlearned reaction to a stimulus


the secretion of an endocrine gland that is transmitted by the blood to the tissue on which it has a specific effect

endocrine system

the system of glands that produce endocrine secretions that help to control bodily metabolic activity

endocrine glands

glands of the endocrine system that release hormones into the bloodstream

pineal gland

gland in the brain which secretes the hormone melatonin, which is involved in sleep-wake cycles


a neural structure lying below the thalamus; directs eating, drinking, body temperature; helps govern the endocrine system via the pituitary gland, and is linked to emotion

pituitary gland

the master gland of the endocrine system, secretes nine hormones which control other glands of the endocrine system

thyroid gland

secretes thyroxin, controls metabolic rate


for glands embedded in the thyroid; secretes hormone which controls level of calcium and phosphate (which influence levels of excitability)


a ductless glandular organ at the base of the neck that produces lymphocytes and aids in producing immunity

adrenal gland

either of a pair of complex endocrine glands situated near the kidney which secrete adrenaline


a large elongated exocrine/endocrine gland located behind the stomach; secretes insulin and glucagon, which are involved in maintaining blood glucose levels

musculoskeletal system

the system of muscles and tendons and ligaments and bones and joints and associated tissues that move the body and maintain its form


rigid connective tissue that makes up the skeleton of vertebrates


one of the contractile organs of the body


strong connective tissue that supports the body and is softer and more flexible than bone


a sheet or band of tough fibrous tissue connecting bones or cartilages or supporting muscles or organs


a cord or band of inelastic tissue connecting a muscle with its bony attachment

connective tissue

tissue that holds organs in place and binds different parts of the body together


self-propelled movement


the internal skeleton


the exterior protective or supporting structure or shell of many animals (especially invertebrates)

skeletal muscle

a muscle that is connected at either or both ends to a bone and so move parts of the skeleton

smooth muscle

a muscle that contracts without conscious control and found in walls of internal organs such as stomach and intestine and bladder and blood vessels (excluding the heart)

cardiac muscle

the muscle tissue of the heart


inflammation of a tendon


a skeletal muscle whose contraction bends a joint


the developmental process of bone formation


whiplike tails found in one-celled organisms to aid in movement


joint inflammation

muscle fatigue

results from oxygen debt -- lactic acid accumulates in skeletal muscles

sensory neurons

carry impulses from the sense organs to the spinal cord and brain

motor neurons

carry impulses from the brain and spinal cord to the muscles and glands; send impulses to the effector in a reflex arc


connect sensory and motor neurons and carry impulses between them

Schwann cells

produce fatty layers of myelin in some neurons

somatic nervous system

division of nervous system responsible for body movements over which an individual has some conscious awareness or voluntary control

autonomic nervous system

division of nervous system which regulates heart rate and controls the contraction of smooth muscles in the digestive system and in blood vessels

reflex arc

the pathway over which nerve impulses travel in a reflex

cerebral palsy

inborn disorder which affects voluntary muscles and speech centers of the brain


inflammation of the membranes surrounding the brain and spinal cord (virus or bacterial infection)


a sudden attack of weakness or paralysis that occurs when blood flow to an area of the brain is interrupted

polio (virus)

an acute viral disease marked by inflammation of nerve cells of the brain stem and spinal cord

exocrine glands

secrete hormones into ducts which carry hormones to where they are needed

feedback mechanism

a mechanism that controls how the endocrine system is activated and deactivated


an enlargement of the thyroid gland that is caused when the thyroid is unable to produce thyroxin due to lack of iodine

diabetes (mellitus)

the inability of the body to remove excess sugar from the blood and store as glycogen in the liver

target cells

the cells that have the receptor for a hormone

steroid hormones

can cross cell membranes easily into the cytoplasm and/or nuclei of target cells; produced from cholesterol

non-steroid hormones

proteins, small peptides, and amino acids that cannot pass through membranes of target cells


hormone-like modified fatty acid produced by a wide range of cells; affects only nearby cells and tissue


male and female reproductive glands

nodes (of Ranvier)

small gaps in the myelin sheath of medullated axons


reproductive cells (sperm and egg cells)


involved in sleep-wake cycles and rythmic activities; secreted by pineal gland


secreted by parathyroid; in charge of raising blood calcium levels


hormone released by adrenal glands; takes up 80% of the adrenal medulla


hormone releases by adrenal glands; takes up 20% of adrenal medulla


secreted by thyroid; increases the rate of protein, carbs, and fat metabolism and the rate of cellular respiration; made up of thyrosine and iodine


hormone secreted by the pancreas; increases levels of glucose in the blood

negative feedback

signals gland secreting hormone to stop production of hormone (ex. hormone that controls glucose levels is released. when glucose levels stabilize, gland producing hormone is signalled to stop)

positive feedback

signals gland secreting hormone to increase hormone production


a protein found in muscle fibers which is involved in contraction and relaxing of muscles; binds to actin


protein found in muscle fibers which is involved in contracton and relaxation of muscles; myosin attaches to it when acetylcholine is present


hormone secreted by the pancreas; decreases levels of glucose in the blood


liquid portion of the blood


a vessel that conveys blood between an artery and a capillary bed


metal that makes blood red in color


found in WBC's but not RBC's

white blood cells

protect the body against invading pathogens


involved in blood clotting

active immunity

the body produces its own antibodies to attack an antigen

passive immunity

only temporary, does not last more than 1 month; the body destroys the borrowed immunity

maternal immunity

mother passes antibodies to her newborn through her breast milk


destroys antibodies made by mother during pregnancy


collapses immune system and kills patient from an opportunistic infection such as pneumonia

autoimmune disorder

when the body fails to recognize some of the body cells as belonging to "self"


an overreaction to an antigen that is normally harmless; histomines are released


disorder of the RBC's; "iron poor"

sickle-cell anemia

a genetic condition in which the RBC's are abnormally shaped


a form of cancer in which a person does not have proper clotting factors


transported within the body from one organ to another


transports blood to the left atrium


flaps of tissue that open and close to prevent backflow of the blood


thick-walled blood vessels that carry blood away from the heart to other parts of the body


thin-walled blood vessels that carry blood back to the heart


tiny, thin-walled blood vessels that allow the exchange of gases and nutrients between the blood and the cells of the body


branches off of the right ventricle and sends oxygenated blood to all parts of the body

pulmonary arteries

send blood to the lungs to get oxygen

vena cavas

returns deoxygenated blood from the body to the right atrium

red blood cells

contain hemoglobin and carry oxygen through the bloodstream


when arteries are clogged with "plaque"

angina pectoris

pains in the chest due to reduced blood flow in the heart


a common treatment for angina pectoris

myocardinal infarction

major blockage in a coronary artery


a virus or organism that can cause disease


abnormal cells multiply uncontrollably, and disrupt normal functioning of one or more organs


any substance that stimulates the production of antibodies


a specialized protein made by the body to fight off future infections from a disease-causing organism


substance prepared from killed or weakened pathogens introduced into a body to produce immunity

coronary artery

branches from the aorta to supply blood to the heart

bicuspid valve

guards the opening between the left atrium and the left ventricle and prevents the blood in the ventricle from returning to the atrium

tricuspid valve

closes when the right ventricle contracts, allowing blood flow into the lungs and prevent backflow into the right atrium

oxygenated blood

enters the left side of the heart and exits through the aorta to the body

deoxygenated blood

carried by pulmonary circulation and enters through the right atrium of the heart from the lungs

nasal cavity

secretes mucus, where incoming air is filtered, warmed, and moistened


thin-walled microscopic air sacs in the lungs where gas exchange occurs


attached to the lower ribs that functions as the main muscle in respiration


the process of drawing air into the lungs


part of the brain that controls breathing rate


inflammation of the linings of the bronchial tubes


contraction of the bronchi due to an allergic response


alveoli enlarge and degenerate and lung capacity increases due to cigarette smoking


a bacterial or viral infection of the lungs where the alveoli fill with fluid

lung cancer

uncontrollable growth of tumors in the lungs

systemic circulation

Circulation of blood throughout the body through arteries, arterioles, capillaries, and veins to deliver oxygen and nutrients to body tissues

pulmonary circulation

Circulation of blood from the pulmonary artery through the vessels in the lungs and back to the heart via the pulmonary vein, providing for the exchange of gases

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