Human Anatomy: Cardiovascular, Lymphatic, Urinary Systems

Cardiovascular System

System responsible for blood circulation in the body.

Heart Contractions

Rate and force adjust to tissue metabolic needs.

Mediastinum

Central thoracic cavity housing the heart and other organs.

Heart Anatomy

Cone-shaped, size of a closed fist.

Base of Heart

Positioned posteriorly and superiorly.

Apex of Heart

Pointed lower part, positioned anteriorly and inferiorly.

Pulmonary Circulation

Right heart pumps blood to lungs for gas exchange.

Systemic Circulation

Left heart pumps oxygenated blood to body tissues.

Fibrous Pericardium

Outer layer preventing heart overdistension.

Serous Pericardium

Inner layer, consists of parietal and visceral parts.

Parietal Pericardium

Lines the fibrous pericardium.

Visceral Pericardium

Covers the heart surface, also called epicardium.

Pericardial Cavity

Space between visceral and parietal pericardia.

Pericardial Fluid

Serous fluid reducing friction during heart movement.

Heart Wall Layers

Composed of epicardium, myocardium, and endocardium.

Epicardium

Superficial layer of the heart wall.

Myocardium

Muscular middle layer responsible for heart contractions.

Endocardium

Inner layer lining the heart chambers.

One-Way Blood Flow

Valves ensure unidirectional blood movement.

Generating Blood Pressure

Heart contractions create pressure for blood movement.

MYOCARDIUM

Thick, muscular middle layer of the heart.

ENDOCARDIUM

Inner layer of heart, smooth for blood flow.

PECTINATE MUSCLES

Muscular ridges in auricles and right atrium.

CRISTA TERMINALIS

Ridge separating smooth atrial wall from pectinate.

TRABECULAE CARNEAE

Muscular ridges in ventricular walls aiding ejection.

CORONARY SULCUS

Groove separating atria from ventricles externally.

ANTERIOR INTERVENTRICULAR SULCUS

Groove on anterior surface between ventricles.

POSTERIOR INTERVENTRICULAR SULCUS

Groove on posterior surface between ventricles.

AURICLES

Flaplike extensions of atria seen anteriorly.

VENA CAVA

Carries blood from body to right atrium.

INFERIOR VENA CAVA

Carries blood from lower body to right atrium.

CORONARY SINUS

Drains blood from heart walls into right atrium.

PULMONARY VEINS

Carry oxygenated blood from lungs to left atrium.

PULMONARY TRUNK

Carries deoxygenated blood from right ventricle to lungs.

AORTA

Carries oxygenated blood from left ventricle to body.

GREAT CARDIAC VEIN

Drains blood from left side of heart.

SMALL CARDIAC VEIN

Drains blood from right margin of heart.

LEFT MARGINAL ARTERY

Supplies blood to lateral wall of left ventricle.

CIRCUMFLEX ARTERY

Supplies blood to posterior wall of the heart.

SYSTOLE

Phase when heart muscle contracts, reducing blood flow.

CORONARY CIRCULATION

Blood vessels supplying heart tissue with blood.

HEART CHAMBERS

Four chambers: two atria and two ventricles.

THIN-WALLED ATRIA

Form anterior parts of the heart.

THICK-WALLED VENTRICLES

Form anterior and inferior parts of the heart.

Diastole

Phase when heart muscle relaxes.

Right Coronary Artery

Supplies blood to right heart regions.

Right Marginal Artery

Branches from right coronary artery, supplies right ventricle.

Posterior Interventricular Artery

Supplies blood to heart's inferior and posterior parts.

Coronary and Systemic Circulation

Oxygen delivery process to heart and muscles.

Oxygen Release

O₂ is delivered to surrounding cells during blood flow.

Resting State O₂ Release

Coronary arteries release about 70% O₂ at rest.

Exercise O₂ Release

Skeletal muscles increase O₂ release to about 70%.

Anastomoses

Direct connections between arteries for blood supply.

Atrioventricular Valves

Ensure blood flows from atria to ventricles.

Tricuspid Valve

AV valve between right atrium and ventricle.

Bicuspid Valve

AV valve between left atrium and ventricle.

Papillary Muscles

Muscles that attach to AV valve cusps.

Chordae Tendineae

Connective tissue strings attaching papillary muscles to valves.

Interatrial Septum

Separates the right and left atria.

Fossa Ovalis

Depression on interatrial septum, former foramen ovale.

Foramen Ovale

Opening between right and left atria in fetus.

Coronary Sinus

Receives blood from the heart itself.

Superior Vena Cava

Receives blood from the upper body.

Inferior Vena Cava

Receives blood from the lower body.

Left Ventricle Thickness

Thicker wall for stronger systemic blood pumping.

Atrioventricular Canal

Pathway between atria and ventricles for blood flow.

Semilunar Valves

Valves between ventricles and great arteries.

Aortic Semilunar Valve

Valve allowing blood from left ventricle to aorta.

Pulmonary Semilunar Valve

Valve allowing blood from right ventricle to pulmonary trunk.

Interventricular Septum

Muscular wall separating left and right ventricles.

Superior Vena Cava

Vein delivering blood from upper body to right atrium.

Inferior Vena Cava

Vein delivering blood from lower body to right atrium.

Tricuspid Valve

Valve preventing backflow into right atrium during contraction.

Bicuspid Valve

Valve preventing backflow into left atrium during contraction.

Pulmonary Arteries

Carry deoxygenated blood from heart to lungs.

Pulmonary Veins

Return oxygenated blood from lungs to left atrium.

Foramen Ovale

Fetal opening allowing blood flow between atria.

Tunica Intima

Inner layer of blood vessel walls.

Blood Flow Route

Pathway of blood circulation through heart chambers.

Right Ventricle

Chamber pumping blood to lungs via pulmonary trunk.

Left Ventricle

Chamber pumping blood to body via aorta.

Cusps

Pocket-like structures in heart valves preventing backflow.

Blood Pressure

Force exerted by circulating blood on vessel walls.

Valve Closure Mechanism

Pressure changes cause valves to open and close.

Oxygenation of Blood

Process of blood picking up oxygen in lungs.

Carbon Dioxide Release

Process of blood releasing CO₂ in lungs.

Endothelium

Thin layer lining blood vessels internally.

Basement Membrane

Supportive layer beneath the endothelium.

Lamina Propria

Thin connective tissue layer in blood vessels.

Blood Vessels

Hollow tubes conducting blood throughout the body.

Internal Elastic Membrane

Fenestrated elastic fiber layer in arteries.

Tunica Media

Middle layer of blood vessels with smooth muscle.

Arteries

Vessels carrying blood away from the heart.

Capillaries

Smallest blood vessels for nutrient exchange.

Veins

Vessels returning blood to the heart.

Vasoconstriction

Smooth muscle contraction reducing vessel diameter.

Vasodilation

Smooth muscle relaxation increasing vessel diameter.

External Elastic Membrane

Layer separating tunica media from tunica adventitia.

Tunica Adventitia

Outer layer of blood vessels, connective tissue.

Elastic Arteries

Largest arteries, first to receive heart blood.