Chapter 15 - Cardiovascular System 12.txt

Angio-

Refers to vessel

Angiotensin

A substance that constricts blood vessels

Ather-

Refers to porridge

Atherosclerosis

Deposits of plaque in arteries

Brady-

Refers to slow

Bradycardia

Abnormally slow heartbeat

Diastol-

Refers to dilation

Diastolic pressure

Blood pressure when the heart ventricle is relaxed

Edem-

Refers to swelling

Edema

Accumulation of fluids causing tissue swelling

-gram

Refers to something written

Electrocardiogram

Recording of electrical changes in the heart during a cycle

Lun-

Refers to moon

Semilunar valve

Valve with crescent-shaped flaps

Myo-

Refers to muscle

Myocardium

Muscle tissue within the heart wall

Papill-

Refers to nipple

Papillary muscle

Mound of muscle projecting into a heart ventricle

Phleb-

Refers to vein

Phlebitis

Inflammation of a vein

Scler-

Refers to hard

Arteriosclerosis

Loss of elasticity and hardening of blood vessel wall

Syn-

Refers to together

Syncytium

Mass of merging cells acting together

Systol-

Refers to contraction

Systolic pressure

Blood pressure from a single ventricular contraction

Tachy-

Refers to rapid

Tachycardia

Abnormally fast heartbeat

Tricuspid Valve

Regulates blood flow between the right atrium and right ventricle

Mitral (Bicuspid) Valve

Located between the left atrium and left ventricle

Aortic Valve

Controls blood flow from the left ventricle into the aorta and the rest of the body

Pulmonary Valve

Controls blood flow from the right ventricle into the pulmonary arteries for oxygenation

Rings of Dense Connective Tissue

Provide attachments for heart valves and muscle fibers, prevent excess dilation of heart chambers

Skeleton of the Heart

Comprised of rings of dense connective tissue and fibrous masses in the interventricular septum

Venae Cavae

Entry points for blood from the systemic circuit into the heart

Pulmonary Trunk

Carries deoxygenated blood from the right ventricle to the lungs

Pulmonary Veins

Carry oxygenated blood from the lungs to the heart

Coronary Arteries

Supply blood to the heart muscle

Cardiac Cycle

Events of a heartbeat coordinated by the heart chambers

Left Ventricular Assist Device (LVAD)

Mechanical half-heart used temporarily until a donor heart is available

Stem Cell Technology

Potential future use in creating 'stem cell heart patches'

Atrial Systole

Contraction of the atria during the cardiac cycle

Ventricular Diastole

Relaxation of the ventricles during the cardiac cycle

Heart Transplant

Replacement of a failing heart with a donor heart

Great Cardiac Vein

Collects deoxygenated blood from the heart muscle

Apex of the Heart

Pointed end of the heart directed downward, forward, and to the left

Cardiac Conduction System

Specialized tissue that initiates and distributes impulses throughout the heart

Intercalated Discs

Contain gap junctions allowing action potentials to spread in cardiac muscle cells

SA node

The first component of the cardiac conduction system responsible for initiating the impulse that starts the cardiac cycle

Atrial syncytium

Where the impulse travels after the SA node in the cardiac conduction system

Junctional fibers

Follow the atrial syncytium in the cardiac conduction pathway

AV node

The component after the junctional fibers in the cardiac conduction system, which delays the impulse before passing to the ventricles

AV bundle

The next component after the AV node in the cardiac conduction system

Bundle branches

Components following the AV bundle in the cardiac conduction system

Purkinje fibers

The component after the bundle branches in the cardiac conduction system, stimulating ventricular muscle cells

Ventricular syncytium

The final component in the cardiac conduction system, causing ventricular contraction

Electrocardiogram (ECG, EKG)

A recording of electrical changes in the heart during the cardiac cycle

P wave

Represents atrial depolarization in an ECG

QRS complex

Represents ventricular depolarization in an ECG

T wave

Represents ventricular repolarization in an ECG

Baroreceptor reflexes

Maintain stable blood pressure by balancing parasympathetic and sympathetic effects

Arrhythmias

Altered heart rhythms

Fibrillation

Chaotic contraction of myocardium

Tachycardia

Abnormally fast heartbeat

Bradycardia

Abnormally slow heartbeat

Flutter

Rapid, regular heart chamber contraction

Premature beat

A beat occurring before expected in the cardiac cycle

Ectopic pacemaker

AV node acting as a secondary pacemaker

Artificial pacemaker

Device treating cardiac conduction disorders

Blood vessels

Organs transporting blood in the cardiovascular system

Arteries

Carry blood away from the heart

Arterioles

Receive blood from arteries and transport it to capillaries

Capillaries

Site of substance exchange between blood and body cells

Venules

Receive blood from capillaries and lead it to veins

Veins

Carry blood back to the heart

Tunica intima

Provides a smooth lining for blood vessel lumens

Tunica media

Controls blood vessel diameter through smooth muscle contraction

Tunica externa

Offers structural support and protection for blood vessels

Valves

Prevent backflow of blood in veins

Angiogenesis

Formation of new blood vessels

Vascular Endothelial Growth Factor (VEGF)

Mainly controls angiogenesis

Lumen

Central cavity through which blood flows in a blood vessel

Tumors

Secrete VEGF to nourish themselves

Antiangiogenesis drugs

Used to treat cancer and age-related macular degeneration

Artery layers

Tunica interna (intima), Tunica media, Tunica externa (adventitia)

Tunica interna

Innermost layer of an artery

Tunica media

Contains smooth muscle and elastic tissue in arteries

Tunica externa

Outer layer of an artery

Arteries vs

Arteries have thicker walls than veins

Arterial function

Transport blood under high pressure

Arteries give rise to

Smaller arterioles

Arterioles vs

Arterioles have thinner walls but same three layers

Arteriole wall changes

Middle and outer layers become thinner as arterioles get smaller

Arterioles and arteries

Both can undergo vasoconstriction and vasodilation

Precapillary sphincter

Regulates blood flow into capillaries

Capillaries

Smallest-diameter blood vessels

Capillary exchange

Mainly by diffusion

Capillary permeability

Semi-permeable

Capillary network density

Higher in tissues with higher metabolic rates

Veins

Thinner walls than arteries, function as blood reservoirs