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Module 15 in the Syllabus

The Cardiovascular System Images
Image gallery for study with links to larger teaching JPEGs for classroom presentation

Question Drill for The Cardiovascular System
Conceptual Vocabulary Self-Test

Basic Terms Crossword Puzzle

Basic Puzzle Solution

Conceptual Vocabulary
Blood vesselBlood vessels are part of the cardiovascular system and function to transport blood throughout the body, the most important types being arteries and veins.
ArteryAn artery is a muscular blood vessel that carries blood away from the heart.
CapillariesCapillaries are the smallest of a body's blood vessels, connecting arterioles to venules
VeinA vein is a blood vessel that carries blood toward the heart.
HeartThe heart is a muscular organ responsible for pumping blood through the blood vessels by repeated, rhythmic contractions.
ArterioleAn arteriole is a small diameter blood vessel that extends and branches out from an artery and leads to capillaries.
VenuleA venule is a small blood vessel that allows deoxygenated blood to return from the capillary beds to the larger blood vessels called veins.
AortaThe aorta is the largest artery in the human body.
Right atriumThe right atrium is one of four chambers in the human heart, receiving de-oxygenated blood from the superior and inferior vena cavae and the coronary sinus and pumping it into the right ventricle through the tricuspid valve.
Right ventricleThe right ventricle is one of four chambers in the human heart, receiving de-oxygenated blood from the right atrium via the tricuspid valve and pumping it into the pulmonary artery via the pulmonary valve.
Left atriumThe left atrium is one of the four chambers in the human heart, receiving oxygenated blood from the pulmonary veins and pumping it into the left ventricle.
Heart valveThe heart valves maintain the unidirectional flow of blood by opening and closing depending on the difference in pressure on each side.
Left ventricleThe left ventricle is one of four chambers in the human heart, receiving oxygenated blood from the left atrium via the mitral valve and pumping it into the aorta via the aortic valve.
Pulmonary arteryThe pulmonary arteries carry blood from the heart to the lungs.
Tricuspid valveThe tricuspid valve is on the right side of the heart, between the right atrium and the right ventricle.
Mitral valveThe mitral valve, also known as the bicuspid valve, is a dual flap valve in the heart that lies between the left atrium and the left ventricle.
Cardiac cycleCardiac cycle is the term referring to all or any of the events related to the flow of blood that occur from the beginning of one heartbeat to the beginning of the next.
Heart rateHeart rate is a term used to describe the frequency of the cardiac cycle.
HypertensionHypertension is a medical condition in which the blood pressure is chronically elevated.
Sinoatrial nodeThe sinoatrial node is the impulse generating pacemaker tissue located in the right atrium of the heart, and thus the generator of sinus rhythm.
Atrioventricular nodeThe atrioventricular node is an area of specialized tissue between the atria and the ventricles of the heart, which conducts the normal electrical impulse from the atria to the ventricles.
Bundle of HisThe bundle of His is a collection of heart muscle cells specialized for electrical conduction that transmits the electrical impulses from the AV node to the point of the apex of the fascicular branches.
Purkinje fibersPurkinje fibers are specialized myocardial fibers located in the inner ventricular walls of the heart that conduct an electrical stimulus or impulse that enables the heart to contract in a coordinated fashion.
EndotheliumThe endothelium is the thin layer of cells that line the interior surface of blood vessels.
Hepatic portal veinThe hepatic portal vein drains blood from the digestive system and its associated glands.
Portal venous systemA portal venous system occurs when a capillary bed drains into another capillary bed through veins.
Pulmonary veinThe pulmonary veins carry oxygen-rich blood from the lungs to the left atrium of the heart.
Aortic valveThe aortic valve is one of the valves of the heart. It lies between the left ventricle and the aorta.
Venae cavaeThe superior and inferior vena cavae are the veins that return de-oxygenated blood from the body into the heart, emptying into the right atrium.
SystoleSystole is the contraction of heart chambers, driving blood out of the chambers.
DiastoleDiastole is the period of time when the heart relaxes after contraction.
Vascular resistanceVascular resistance is a term used to define the resistance to flow that must be overcome to push blood through the circulatory system.
VasoconstrictorA vasoconstrictor, also vasopressor or simply pressor, is any substance that acts to cause vasoconstriction and usually results in an increase of the blood pressure.
Peripheral arteriesPeripheral arteries are the arteries which are furthest from the heart.
SinusoidA sinusoid is a small blood vessel similar to a capillary but with a discontinuous endothelium.
HypotensionHypotension refers to an abnormally low blood pressure.
Sinus rhythmSinus rhythm is a term used in medicine to describe the normal beating of the heart, as measured by an electrocardiogram (ECG).
VasodilatorA vasodilator is a drug or chemical that relaxes the smooth muscle in blood vessels, which causes them to dilate.
Cardiac action potentialThe cardiac action potential is a specialized action potential in the heart, with unique properties necessary for function of the electrical conduction system of the heart.
Tunica externaThe tunica externa, previously known as the tunica adventitia, is the outermost layer of a blood vessel, surrounding the tunica media.
Tunica mediaThe tunica media is the middle layer of an artery or vein
Tunica intimaThe tunica intima is the innermost layer of an artery.
Superficial veinSuperficial vein is a term used to describe a vein that is close to the surface of the body.
MyocardiumMyocardium is the muscular tissue of the heart.
Atrial fibrillationAtrial fibrillation is a cardiac arrhythmia that involves the two atria of the heart.
ElectrocardiogramA electrocardiogram (ECG or EKG) is a graphic produced by an electrocardiograph, which records the electrical activity of the heart over time.
Cardiac outputCardiac output is the volume of blood being pumped by the heart, in particular by a ventricle in a minute.
Stroke volumeStroke volume is the amount of blood pumped by the left ventricle of the heart in one contraction.
End-systolic volumeEnd-systolic volume is the volume of blood in the ventricles just after systole.
Advanced terms that may appear in context in MCAT passages
End-diastolic volumeEnd-diastolic volume is the volume of blood in a ventricle at the end of filling.
BaroreflexThe baroreflex or baroreceptor reflex is one of the body's homeostatic mechanisms for maintaining blood pressure, in which an elevated blood pressure reflexively causes blood pressure to decrease.
Jugular veinThe jugular veins are veins that bring deoxygenated blood from the head back to the heart via the superior vena cava.
Superior vena cavaThe superior vena cava is a large, short vein that carries de-oxygenated blood from the upper half of the body to the heart's right atrium.
Inferior vena cavaThe inferior vena cava is the large vein that carries de-oxygenated blood from the lower half of the body into the heart.
Interventricular septumThe interventricular septum is the stout wall separating the ventricles of the heart from one another.
Coronary sinusThe coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the myocardium of the heart.
ChronotropicChronotropic effects are those that change the heart rate.
Systemic venous systemThe systemic venous system describes the veins that drain into the right atrium without passing through two vascular beds before reaching the right side of the heart.
EndocardiumThe endocardium is the innermost layer of tissue that lines the chambers of the heart.
EpicardiumEpicardium describes the outer layer of heart tissue.
PreloadPreload is the pressure stretching the ventricle of the heart, after passive filling and atrial contraction.
Frank-Starling law of the heartStarling's law states that the more the ventricle is filled with blood during diastole, the greater the volume of ejected blood will be during the resulting systolic contraction.
DromotropicA dromotropic agent is one which affects the conduction velocity of the AV node, and subsequently the rate of electrical impulses in the heart.

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