EKG Test Review: Cardiovascular System Vocabulary

Vocabulary flashcards covering key cardiovascular and blood-related terms from the lecture notes.

Cardiovascular system

The system that transports hormones and wastes throughout the body and helps regulate body temperature.

Formed elements (blood)

The solid components of blood: leukocytes, erythrocytes, and thrombocytes.

Leukocytes

White blood cells; part of the immune system.

Erythrocytes

Red blood cells; carry oxygen via hemoglobin.

Thrombocytes

Platelets; cell fragments essential for blood clotting.

Plasma

The liquid component of blood, about 55% of blood volume, mostly water.

Hemoglobin

A protein in red blood cells that binds and carries oxygen.

Thrombopoietin

Hormone that stimulates platelet production.

Hemostasis

The process of stopping bleeding, including vascular spasm and platelet plug formation.

Vasoconstriction

Narrowing of a blood vessel to reduce blood loss.

Platelet plug formation

Platelets activate and form a mesh that seals small vessel injuries.

A positive (A+) blood type

Blood type with A antigens and Rh antigen on red blood cells.

AB blood type

Has A and B antigens with Rh antigen; universal recipient for transfusions.

Arteries

Blood vessels that carry blood away from the heart; typically high-flow vessels.

Capillaries

Small vessels where gas exchange occurs; have the smallest overall flow and cross-sectional area.

Inferior vena cava

Large vein returning deoxygenated blood from the lower body to the right atrium.

Right atrium

Heart chamber that receives blood from the body via the vena cavae.

Aorta

Main artery that carries oxygenated blood from the left ventricle to the body.

Embolus

A moving clot traveling through the bloodstream.

Thrombus

A stationary blood clot formed within a vessel.

SA Node

Sinoatrial node; the natural pacemaker of the heart.

AV Node

Atrioventricular node; conducts impulse from atria to ventricles.

AV Bundle (Bundle of His)

Pathway transmitting impulses from the AV node to bundle branches.

Bundle Branches

Pathways carrying impulses through the interventricular septum to Purkinje fibers.

Purkinje fibers

Conduction fibers that distribute impulses to ventricles to trigger contraction.

Type B blood

Blood type with B antigens on red blood cells; can receive B or O.

Epicardium

Outer heart layer (visceral pericardium); reduces friction and contains lubricating fluid.

Myocardium

Thick muscular middle layer of the heart that contracts to pump blood.

Endocardium

Inner lining of the heart chambers; smooth to prevent clots.

Pulmonary circuit

Circulation from the heart to the lungs and back.

Systemic circuit

Circulation from the heart to the body and back.

Ejection phase (systole)

Phase of the cardiac cycle when ventricles contract to eject blood.

Tunica layers (arteries/veins)

Three layers: tunica intima, tunica media, tunica externa.

Septum

Wall that divides the heart’s chambers into left and right sides.

Systole

Contraction phase of the heart.”

Diastole

Relaxation phase