Heart and Blood Vessels Condensed Flashcards

Vocabulary flashcards covering the cardiovascular system, blood vessels, lymphatic system, heart anatomy, cardiac cycle, conduction, ECG, blood pressure regulation, and physiological formulas.

Cardiovascular system

The organ system made of the heart, blood vessels, and blood that transports substances throughout the body.

Heart

A muscular organ that creates pressure to pump blood through the pulmonary and systemic circuits.

Blood vessels

Tubes that carry blood between the heart and body tissues.

Blood

A fluid connective tissue that transports gases, nutrients, wastes, hormones, heat, and immune components.

Homeostasis

Maintenance of a relatively stable internal environment despite internal or external changes.

Pulmonary circuit

The pathway that carries blood from the right side of the heart to the lungs and back to the left side of the heart.

Systemic circuit

The pathway that carries blood from the left side of the heart to the body and back to the right side of the heart.

Oxygenated blood

Blood with a relatively high oxygen concentration after passing through the lungs.

Deoxygenated blood

Blood with a relatively low oxygen concentration after delivering oxygen to systemic tissues.

Artery

A blood vessel that carries blood away from the heart.

Arteriole

A small artery and major resistance vessel that controls blood flow into capillary beds.

Capillary

A microscopic vessel with a wall only one endothelial cell thick where exchange occurs between blood and tissues.

Capillary bed

An extensive network of capillaries that increases exchange surface area and reduces diffusion distance.

Venule

A small vessel that receives blood from capillaries and merges with other venules to form veins.

Vein

A blood vessel that carries blood toward the heart and acts as a blood-volume reservoir.

Lumen

The hollow internal space through which blood flows inside a vessel.

Vascular valve

A one-way flap, especially common in limb veins, that prevents the backward flow of blood.

Tunic

One of the three tissue layers forming the wall of an artery or vein.

Tunica intima or tunica interna

The innermost vessel layer, consisting mainly of endothelium and a small amount of connective tissue.

Endothelium

The simple squamous epithelial lining of blood vessels and the heart's inner surface.

Tunica media

The middle vessel layer of smooth muscle and elastic fibers that changes vessel diameter.

Vascular smooth muscle

Involuntary muscle in vessel walls that produces vasoconstriction or vasodilation.

Tunica externa or adventitia

The outer connective-tissue vessel layer that protects and anchors the vessel.

Elastic artery

A large artery, such as the aorta, that stretches during systole and recoils during diastole to maintain blood flow.

Muscular artery

An artery with substantial smooth muscle that distributes blood to a particular organ or body region.

Resistance vessel

A vessel, mainly an arteriole, whose diameter strongly controls vascular resistance and tissue blood flow.

Vasodilation

Relaxation of vascular smooth muscle that widens a vessel, lowers resistance, and usually increases downstream blood flow.

Vasoconstriction

Contraction of vascular smooth muscle that narrows a vessel, raises resistance, and usually reduces downstream blood flow.

Peripheral resistance

Opposition to blood flow in systemic vessels, especially arterioles.

Precapillary sphincter

A ring of smooth muscle that regulates blood entry from an arteriole or metarteriole into a true capillary.

Perfusion

Delivery of blood to a tissue or organ.

Diffusion

Passive movement of particles from an area of higher concentration to an area of lower concentration.

Filtration

Movement of fluid out of a capillary due mainly to capillary hydrostatic pressure.

Capillary hydrostatic pressure

The pressure of blood against a capillary wall that pushes water and small solutes outward.

Reabsorption

Movement of fluid from interstitial space back into a capillary, promoted by plasma proteins.

Compliance

The ability of a vessel to expand when the volume or pressure of blood increases.

Capacitance vessel

Another name for a vein because veins can store a large amount of blood at low pressure.

Varicose vein

An enlarged, twisted superficial vein caused partly by ineffective valves and blood pooling.

Venous return

The flow of blood through the veins back to the heart.

Skeletal-muscle pump

The squeezing of veins by contracting skeletal muscles, which moves blood toward the heart while valves prevent backflow.

Respiratory pump

Pressure changes during breathing that help move venous blood from the abdomen toward the thorax and heart.

Aneurysm

An abnormal localized outward bulge produced by weakening of an arterial wall.

Aortic aneurysm

An aneurysm located in the aorta that may cause fatal internal bleeding if it ruptures.

Aortic dissection

Separation of the aortic wall layers when blood enters through a tear in the inner wall.

Plaque

A buildup of lipids and other materials in an arterial wall that can narrow the lumen.

Blood clot or thrombus

A mass of coagulated blood that can obstruct blood flow.

Interstitial fluid

Fluid surrounding body cells that forms from fluid filtered out of blood capillaries.

Lymphatic system

A vessel and organ network that returns excess interstitial fluid to the blood and contributes to immune defense.

Lymphatic capillary

A microscopic blind-ended vessel that collects interstitial fluid, proteins, pathogens, and debris.

Lymph

Interstitial fluid after it has entered a lymphatic vessel.

Lymphatic vessel

A thin-walled, valved vessel that transports lymph toward larger lymphatic ducts.

Lymph node

An immune structure that filters lymph and contains lymphocytes and other immune cells.

Right lymphatic duct

A duct that returns lymph from the right upper portion of the body to venous blood.

Thoracic duct

The largest lymphatic duct, returning lymph from most of the body to venous blood.

Edema

Swelling caused by excess fluid accumulating in interstitial spaces.

Mediastinum

The central compartment of the thoracic cavity between the lungs where the heart is located.

Apex of the heart

The pointed inferior part of the heart directed mainly downward and to the left.

Base of the heart

The broad superior region of the heart where the major vessels attach.

Pericardium

The double-walled sac that protects and anchors the heart while allowing movement.

Fibrous pericardium

The tough outer connective-tissue layer of the pericardium.

Serous pericardium

The thin double-layered membrane consisting of parietal and visceral layers.

Parietal serous pericardium

The serous layer lining the inner surface of the fibrous pericardium.

Visceral serous pericardium

The serous layer directly covering the heart; it is also called the epicardium.

Pericardial cavity

The small potential space between the parietal and visceral serous pericardial layers.

Epicardium

The outer heart-wall layer, identical to the visceral serous pericardium.

Myocardium

The thick middle heart-wall layer of cardiac muscle that contracts to pump blood.

Endocardium

The thin endothelial and connective-tissue layer lining the heart chambers and valves.

Atrium

An upper heart chamber that receives blood returning to the heart.

Ventricle

A lower heart chamber that pumps blood out of the heart.

Right atrium

The chamber receiving deoxygenated blood from the superior vena cava, inferior vena cava, and coronary sinus.

Right ventricle

The chamber pumping deoxygenated blood through the pulmonary valve into the pulmonary trunk.

Left atrium

The chamber receiving oxygenated blood from the pulmonary veins.

Left ventricle

The thick-walled chamber pumping oxygenated blood through the aortic valve into the aorta.

Interatrial septum

The wall separating the right and left atria.

Interventricular septum

The wall separating the right and left ventricles and containing part of the conduction pathway.

Superior vena cava or SVC

The large vein returning deoxygenated blood from the head, neck, upper limbs, and upper thorax to the right atrium.

Inferior vena cava or IVC

The large vein returning deoxygenated blood from below the diaphragm to the right atrium.

Coronary sinus

The large venous channel that receives most cardiac venous blood and empties into the right atrium.

Heart valve

A structure that opens or closes in response to pressure differences to ensure one-way blood flow through the heart.

Atrioventricular valve or AV valve

A valve between an atrium and ventricle; the tricuspid and mitral valves are AV valves.

Tricuspid valve or right AV valve

The valve between the right atrium and right ventricle that prevents backflow into the right atrium.

Mitral valve, bicuspid valve, or left AV valve

The valve between the left atrium and left ventricle that prevents backflow into the left atrium.

Semilunar valve

A valve between a ventricle and a great artery; the pulmonary and aortic valves are semilunar valves.

Pulmonary semilunar valve

The valve between the right ventricle and pulmonary trunk that prevents backflow into the right ventricle.

Aortic semilunar valve

The valve between the left ventricle and aorta that prevents backflow into the left ventricle.

Chordae tendineae

Tough connective-tissue cords attaching AV valve cusps to papillary muscles.

Papillary muscle

A ventricular muscle projection that tightens the chordae tendineae during ventricular systole.

Valve prolapse

Abnormal bulging of a valve cusp backward into an atrium during ventricular contraction.

Valve stenosis

Narrowing of a valve opening that obstructs forward blood flow.

Valve regurgitation

Backward leakage of blood through a valve that does not close completely.

Pulmonary trunk

The large vessel leaving the right ventricle and dividing into the right and left pulmonary arteries.

Pulmonary artery

An artery carrying deoxygenated blood away from the right ventricle toward a lung.

Pulmonary capillary

A microscopic lung vessel where blood releases carbon dioxide and gains oxygen.

Pulmonary vein

A vein carrying oxygenated blood from a lung to the left atrium.

Aorta

The largest systemic artery, carrying oxygenated blood from the left ventricle to the body.

Brachiocephalic artery

The first branch of the aortic arch, supplying the right upper limb and right side of the head and neck through its branches.

Left common carotid artery

An aortic-arch branch supplying the left side of the head and neck.

Left subclavian artery

An aortic-arch branch supplying the left upper limb and contributing to thoracic and brain circulation.

Coronary circulation

The blood supply serving the myocardium itself.

Coronary artery

An artery arising from the ascending aorta that supplies oxygenated blood to the myocardium.