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Anatomy & Physiology Anatomy of the Cardiovascular System

Anatomy & Physiology Anatomy of the Cardiovascular System

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Page 1: Anatomy & Physiology Anatomy of the Cardiovascular System

Anatomy & Physiology

Anatomy of the Cardiovascular System

Page 2: Anatomy & Physiology Anatomy of the Cardiovascular System

Heart songhttp://www.youtube.com/watch?v=q0s-

1MC1hcE

Page 3: Anatomy & Physiology Anatomy of the Cardiovascular System

Location of the heartIn mediastinum

behind the sternum between 2nd & 6th ribs. Shifted to left.

Posteriorly between 5th to 8th thoracic vertebrae

Apex (lowest point) lies on diaphragm

Page 4: Anatomy & Physiology Anatomy of the Cardiovascular System

PericardiumSac covering the heart

Fibrous pericardium – tough, inelastic

Serous pericardium- 2 layersParietal layer- lines fibrous

pericardiumVisceral layer (epicardium)-

adheres to outside of heart; space between parietal & visceral layer contain small amount of fluid

Page 5: Anatomy & Physiology Anatomy of the Cardiovascular System

Function of pericardiumProvides protection against friction

Page 6: Anatomy & Physiology Anatomy of the Cardiovascular System

Layers of the heartEpicardium (also the serous pericardium)Myocardium-thick contractile layer of muscle

cellsEndocardium-cover trabeculae (muscular

projections); specialized folds of endocardium make up the major valves of heart

Page 7: Anatomy & Physiology Anatomy of the Cardiovascular System

Chambers of heart

Atria: upper chambers

Ventricles: lower chambers

Chambers are separated by an extension of heart wall, septum

Page 8: Anatomy & Physiology Anatomy of the Cardiovascular System

Atria

Receive blood from veins

Send blood to ventricles

Thin myocardial wall

Auricle: earlike flap protruding from each atrium

Page 9: Anatomy & Physiology Anatomy of the Cardiovascular System

Ventricles

Receive blood from the atria

Pump blood out of heart into arteries

Thicker myocardium

Myocardium of left ventricle thicker than right ventricle

Page 10: Anatomy & Physiology Anatomy of the Cardiovascular System

Heart valves

Permit flow of blood in one directionAtrioventricular valves

Semilunar valves

Page 11: Anatomy & Physiology Anatomy of the Cardiovascular System

Atrioventricular valves

Made of flaps of endocardium

Flaps anchored to papillary muscle by chordae tendineae

Rt AV valve: tricuspid valve

Lt AV valve: mitral (bicuspid) valve

Page 12: Anatomy & Physiology Anatomy of the Cardiovascular System

Semilunar valves

Consists of half moon shaped flaps

Pulmonary semilunar valve: at the entrance to the pulmonary artery

Aortic semilunar valve: at the entrance to aorta

Page 13: Anatomy & Physiology Anatomy of the Cardiovascular System

Flow of blood through the heart

Page 14: Anatomy & Physiology Anatomy of the Cardiovascular System

Heart videohttp://www.youtube.com/watch?

v=DAXa4eR1s0M

Page 15: Anatomy & Physiology Anatomy of the Cardiovascular System

Blood supply to heart Blood supplied thru the right & left coronary arteries

Coronary arteries are first branches off aorta

After blood has passed thru capillary beds, enters cardiac veins then thru common channel, coronary sinus, then into rt atrium

Page 16: Anatomy & Physiology Anatomy of the Cardiovascular System

Conduction system of heartSinoatrial node (pacemaker): in rt atrium

near opening of superior vena cavaAtrioventricular node: in rt atrium along

lower part of interatrial septumAtrioventricular bundle: originate in AV

node & extend by 2 branches thru the 2 sides of the interventricular septum

Purkinje fibers: extension of AV bundle out to the lateral walls of the ventricles & papillary muscles

Page 17: Anatomy & Physiology Anatomy of the Cardiovascular System

Conduction System

Page 18: Anatomy & Physiology Anatomy of the Cardiovascular System

Blood vesselsArteries: carry blood away from heartArterioles: small arteries

Veins: Carry blood toward heartVenules: small veins

Capillaries: microscopic blood vessels that carry blood from arterioles to venules

Page 19: Anatomy & Physiology Anatomy of the Cardiovascular System

3 layers of blood vessels

Tunica adventitia: outer layer, fibrous connective tissue

Tunica media: layer of smooth muscle & elastic connective tissue

Tunica intima: made of smooth endothelium

Page 20: Anatomy & Physiology Anatomy of the Cardiovascular System

Blood Vessel StructureType of vessel

Tunica intima

Tunica media

Tunica adventitia

artery Smooth lining

Thicker than in veins

Thinner than tunica media

vein Smooth lining with valves

Thinner than in arteries

Thicker than tunica media

capillary Makes up entire wall: very thin

absent absent

Page 21: Anatomy & Physiology Anatomy of the Cardiovascular System

Functions of capillaries

Transport materials to and from cells

Capillaries so numerous & so small that blood flows at its slowest rate in capillaries

Page 22: Anatomy & Physiology Anatomy of the Cardiovascular System

Functions of arteries

Function as “distributors”

Arterioles also function as resistance vessels

Smooth muscle cells on arterioles act as precapillary sphincters where a capillary originates

Page 23: Anatomy & Physiology Anatomy of the Cardiovascular System

Functions of veinsReturn blood to heartAct as reservoir vesselsAbility to stretch by veins called capacitance thus veins are capacitance vessels

Page 24: Anatomy & Physiology Anatomy of the Cardiovascular System

Circulatory routes

Systemic circulation: blood flow from heart to all parts of body (except lungs)

Pulmonary circulation: blood flow from heart to lungs

Page 25: Anatomy & Physiology Anatomy of the Cardiovascular System

ArteriesEnd-arteries: most of the arteries, they diverge into capillaries

A few arteries open into branches of other arteries; this communication is an arterial anastomosis

Incidence of arterial anastomosis increases as distance from the heart increases

Page 26: Anatomy & Physiology Anatomy of the Cardiovascular System

AortaMajor artery that

serves as trunk of the entire systemic arterial system

First few cm conducts blood up away from lt ventricle-ascending aorta

Then turns 180 degrees-aortic arch

Then downward from arch-descending aorta

Page 27: Anatomy & Physiology Anatomy of the Cardiovascular System

Veins

Large veins that return blood to heart in systemic circulation are superior & inferior vena cava