Heart LaboratoryHeart Laboratory

Circulatory SystemCirculatory SystemOrgans and Cells Organs and Cells Organization and FunctionsOrganization and Functions

Circulatory SystemCirculatory System• Heart Heart

4 chambers: 2 atria + 2 ventricles4 chambers: 2 atria + 2 ventricles– Blood flow regulated by valves:Blood flow regulated by valves:

2 atrioventricular + 2 semilunar 2 atrioventricular + 2 semilunar

• Blood VesselsBlood Vessels– arteries and veinsarteries and veins– arterioles and venulesarterioles and venules– capillaries capillaries

(c)(c) Mammals,Mammals,BirdsBirds

(b) “Herptiles”(b) “Herptiles”

The Evolution of the Vertebrate HeartThe Evolution of the Vertebrate Heart

VentricleVentricle

AtriumAtrium

(a) Fish(a) Fish GillGillCapillariesCapillaries

Body CapillariesBody Capillaries

VentricleVentricle

LungLungCapillariesCapillaries

AtriaAtria

Body CapillariesBody Capillaries

VentriclesVentricles

LungLungCapillariesCapillaries

Body CapillariesBody Capillaries

LeftLeftVentricleVentricle

Human Heart

SemilunarSemilunarValvesValves

AortaAorta

Descending AortaDescending Aorta(to lower body)(to lower body)Inferior Vena CavaInferior Vena Cava

(from lower body)(from lower body)

RightRightAtriumAtrium

SuperiorSuperiorVena CavaVena Cava(from upper body)(from upper body)

Pulmonary ArteryPulmonary Artery(to right lung)(to right lung)

Pulmonary ArteryPulmonary Artery(to left lung)(to left lung)

AtrioventricularAtrioventricularValveValve

Right VentricleRight Ventricle

Pulmonary VeinsPulmonary Veins(from right lung)(from right lung)

Pulmonary VeinsPulmonary Veins(from left lung)(from left lung)

Left AtriumLeft Atrium

AtrioventricularAtrioventricularValveValve

The Cardiac CycleThe Cardiac Cycle

Atria ContractAtria Contract

DeoxygenatedDeoxygenatedblood from bodyblood from body

OxygenatedOxygenatedblood from lungsblood from lungs

Ventricles ContractVentricles Contract

DeoxygenatedDeoxygenatedblood to lungsblood to lungs

OxygenatedOxygenatedblood to bodyblood to body

Heart Relaxes;Heart Relaxes;atria fill passivelyatria fill passively

FibrousFibrouspericardiumpericardium

Visceral Visceral pericardiumpericardiumLayers of Heart TissueLayers of Heart Tissue

Structure of the HeartStructure of the Heart

Three Layers of tissueThree Layers of tissue

Endocardium- liningEndocardium- lining

Myocardium- Myocardium- musclemuscle

Pericardium- Pericardium- outside outside

The Structure of Cardiac MuscleThe Structure of Cardiac Muscle

Two views of coronary arteries and veinsTwo views of coronary arteries and veins

Blood Flow to the HeartBlood Flow to the Heart

Coronary Arteries and VeinsCoronary Arteries and Veins

The Heart’s Pacemakerand Its Connections

Sinoatrial (SA) Sinoatrial (SA) NodeNode

Atrioventricular Atrioventricular (AV) Node(AV) Node

ExcitableExcitableFibersFibers

SA Node = pacemaker

AV Node receives signals from SA node, sends signal through excitable fibers for ventricles to beat simultaneously

Heart FunctionHeart Function

Heartbeat Heartbeat visualized visualized with ECGwith ECG

Atria Contract

VentriclesRelax

Atria RelaxVentriclesContract

AtrioventricularValves Close“lubb” sound

SemilunarValves Close“dup” sound

Blood PressureBlood Pressure

Blood pressure =Blood pressure = Systolic pressureSystolic pressure Diastolic pressureDiastolic pressure

Systolic: pressure during Systolic: pressure during ventricular contractionventricular contraction

Diastolic: pressure during Diastolic: pressure during ventricular relaxationventricular relaxation

ArteryArtery

VeinVein

ArterioleArteriole

PrecapillaryPrecapillarySphinctersSphincters

CapillariesCapillaries

VenuleVenule

EndotheliumEndotheliumConnectiveTissueConnectiveTissue

MuscleMuscle

ConnectiveConnective Tissue Tissue

Structures and Interconnections of Blood Vessels

•Arteries carry blood away from the heartVeins carry blood back to the heart

Blood Return Through Veins Blood Return Through Veins

• Skeletal muscles Skeletal muscles help return blood help return blood to the heartto the heart

• Valves prevent Valves prevent back-flowback-flow

Blood ComponentsBlood Components

Red blood cellsRed blood cellscarry oxygencarry oxygen

White blood cellsWhite blood cellsdefend against invadersdefend against invaders

Platelets initiatePlatelets initiateblood clottingblood clotting

Plasma is the fluid Plasma is the fluid portion of blood.portion of blood.

Lipid Carriers distributeLipid Carriers distributetriglycerides and cholesterol.triglycerides and cholesterol.

LDL = low density lipoproteinLDL = low density lipoprotein delivers cholesterol delivers cholesterol

HDL= high density lipoproteinHDL= high density lipoprotein returns cholesterol to returns cholesterol to liver for destruction liver for destruction

Functions of Functions of Blood Blood • Supplies nutrientsSupplies nutrients• Removes wastesRemoves wastes• Equalizes temperatureEqualizes temperature• Transports hormones and antibodiesTransports hormones and antibodies

DiseasesDiseases

• HypertensionHypertension• AtherosclerosisAtherosclerosis• StrokeStroke• Heart Attack Heart Attack

WorksheetWorksheet

• Complete pages 137-138 from lab Complete pages 137-138 from lab manualmanual

• Be sure your instructor checks your Be sure your instructor checks your completed worksheet before you completed worksheet before you leave the lableave the lab