Circulatory SystemCirculatory System

You Gotta Have HeartYou Gotta Have Heart

The Circulatory SystemThe Circulatory System

Circulatory System Consists Circulatory System Consists of…of…

Blood VesselsBlood Vessels

BloodBlood

HeartHeart

OverviewOverview The Heart pumps blood through The Heart pumps blood through

the body through blood vessels the body through blood vessels ((arteries, capillaries and veinsarteries, capillaries and veins))

ArteriesArteries take blood away from take blood away from the heart, veins return blood to the heart, veins return blood to the heartthe heart

Blood carries OBlood carries O22 (food) towards (food) towards and COand CO22 (waste) away from tissues (waste) away from tissues

The lungs are not part of the The lungs are not part of the circulatory system!!circulatory system!!

Circulatory SystemCirculatory System

BLOOD VESSELSBLOOD VESSELS

Two PathwaysTwo Pathways

PulmonaryPulmonary CirculationCirculation– Carries blood to lungs Carries blood to lungs

and backand back

SystemicSystemic Circulation Circulation– Carries blood to body Carries blood to body

and backand back

Your Blood Vessels: Your Blood Vessels: Pathway of CirculationPathway of Circulation

3 types of vessels3 types of vessels– ArteriesArteries (mostly (mostly

shown as Red shown as Red because blood has Obecause blood has O22))

– CapillariesCapillaries (Red and (Red and Blue because some OBlue because some O22 lost to tissues)lost to tissues)

– VeinsVeins (mostly shown (mostly shown as Blue because Oas Blue because O22 lost to tissues)lost to tissues)

Red Blood and Blue BloodRed Blood and Blue Blood Blood is never blue!!!!!!!!!!!!!!!!!!Blood is never blue!!!!!!!!!!!!!!!!!! Oxygenated blood is bright red and Oxygenated blood is bright red and

deoxygenated blood is dark reddeoxygenated blood is dark red Veins appear blue because of the way Veins appear blue because of the way

light reflects off the blood vessellight reflects off the blood vessel We don’t see arteries because they We don’t see arteries because they

are too deep.are too deep. We draw them blue to distinguish We draw them blue to distinguish

them on diagrams and simplify thingsthem on diagrams and simplify things

Arteries vs. VeinsArteries vs. Veins

What you need to know about the STRUCTURAL differences between Arteries and Veins:

-Artery walls are much thicker, are very elastic and have more muscle

-Veins are thin walled and contain valves to push the blood along

Arteries vs. VeinsArteries vs. Veins

Why are arteries and veins the Why are arteries and veins the way they are?way they are?– Blood is under very high pressure Blood is under very high pressure

when it leaves the heart and enters when it leaves the heart and enters the arteriesthe arteries Therefore, Therefore, arteries need to be arteries need to be

strongstrong!!!!

– Once it has left the tissues and Once it has left the tissues and enters the veins, the blood is under enters the veins, the blood is under a very low pressurea very low pressure Therefore, Therefore, veins are weakveins are weak

Arteries:Arteries:Carry blood Carry blood Away from heartway from heart

– LargeLarge– Thick-walled, MuscularThick-walled, Muscular– ElasticElastic– Oxygenated blood Oxygenated blood

Exception Pulmonary ArteryException Pulmonary Artery

– Carried under great pressureCarried under great pressure– Steady pulsating (used to measure Steady pulsating (used to measure

pulse)pulse)ArteriolesArterioles: smaller vessels, enter tissue: smaller vessels, enter tissue

CapillariesCapillaries

– Smallest vesselSmallest vessel– MicroscopicMicroscopic– Walls one cell Walls one cell

thickthick– Located at the tissueLocated at the tissue– Nutrients and gases Nutrients and gases

(O(O22, CO, CO22) diffuse ) diffuse here here

Veins:Veins:Carry blood to the heart

– Carries blood that Carries blood that contains waste and COcontains waste and CO22

Exception pulmonary veinException pulmonary vein

– Blood under low Blood under low pressurepressure

– ValvesValves to prevent back to prevent back flow due to gravityflow due to gravity

VenulesVenules: small veins, larger : small veins, larger than capillariesthan capillaries

Mechanism of Vein and Varicose Veins Videos

Blood VesselsBlood Vessels

Animation of blood flow

The Aorta – The largest blood The Aorta – The largest blood vesselvessel

Blood Vessel Animation

Blood VesselsBlood VesselsBlood flow is like a round trip to grandma’s houseBlood flow is like a round trip to grandma’s house- You leave your home (The Heart)- You leave your home (The Heart)- You jump on the Highway (Arteries)You jump on the Highway (Arteries)- You get off at grandma’s street (Arterioles)You get off at grandma’s street (Arterioles)- You pull in to grandma’s driveway (capillaries) You pull in to grandma’s driveway (capillaries) - You go inside her house (The Cell) and give her a kiss (Glucose You go inside her house (The Cell) and give her a kiss (Glucose

and Oxygen)and Oxygen)- You leave with leftovers (COYou leave with leftovers (CO22))

- Get back into your car and exit driveway (capillaries)Get back into your car and exit driveway (capillaries)- You drive back along her street (Venuoles)You drive back along her street (Venuoles)- You get back on the highway (Veins) You get back on the highway (Veins) - Arrive back at home (The Heart)Arrive back at home (The Heart)

End of Day 1End of Day 1

Circulatory SystemCirculatory System

BLOODBLOOD

The BloodThe Blood

Body contains 4-6 Body contains 4-6 LL

Consists of Consists of – WaterWater– Red Blood CellsRed Blood Cells– PlasmaPlasma– White blood cells White blood cells

and plateletsand platelets

Your Blood: Fluid TransportYour Blood: Fluid TransportLiquid Portion Carries Liquid Portion Carries

Blood cells (Blood cells (made in bone made in bone marrowmarrow))

– Erythrocytes (RBC - red blood Erythrocytes (RBC - red blood cells)cells)

– Leucocytes (WBC - white Leucocytes (WBC - white blood cells) blood cells)

Platelets (fragments of the cells Platelets (fragments of the cells in bone marrow – no nucleus)in bone marrow – no nucleus)

ProteinsProteins Nutrients - Nutrients - Digestive SystemDigestive System Gases - Gases - Respiratory SystemRespiratory System

Oxygen in the BloodOxygen in the Blood

HemoglobinHemoglobin, iron , iron containing molecule containing molecule – – found in RBC found in RBC

Loosely picks up Loosely picks up oxygen in the lungsoxygen in the lungs

Releases oxygen in Releases oxygen in areas low in oxygen areas low in oxygen – – body tissuesbody tissues

O2

O2

O2O2

Carbon Dioxide in the BloodCarbon Dioxide in the Blood

Hemoglobin Hemoglobin also carries COalso carries CO22

COCO2 2 is a waste product of cellular is a waste product of cellular respirationrespiration

Travels to the lungs to be Travels to the lungs to be exhaledexhaled

What does blood contain?What does blood contain?

50% Water50% Water

45% Erythrocytes (RBC)45% Erythrocytes (RBC)

4% Plasma with Substances4% Plasma with Substances

1% Leukocytes (WBC) + 1% Leukocytes (WBC) + PlateletsPlatelets

Erythrocytes (RBC)Erythrocytes (RBC) Transporters ofTransporters of

– OxygenOxygen– Carbon DioxideCarbon Dioxide

RBCRBC– Lack a nucleusLack a nucleus– Contain hemoglobinContain hemoglobin– Disk-shapedDisk-shaped

RBC are produced in the RBC are produced in the bone marrowbone marrow

Lives for ~120 daysLives for ~120 days Old RBC are destroyed in Old RBC are destroyed in

liver and spleenliver and spleen

Leukocytes (WBC)Leukocytes (WBC)

WBC fight infectionWBC fight infection– Attack foreign Attack foreign

substancessubstances Less abundantLess abundant Created in the Created in the

bone marrowbone marrow Some live for Some live for

monthsmonths– Most just a few daysMost just a few days

Several typesSeveral types ALL contain nucleiALL contain nuclei

PlateletsPlatelets

PLATELETS are for PLATELETS are for CLOTTING bloodCLOTTING blood

Cell fragmentsCell fragments Produced in bone Produced in bone

marrowmarrow Short life span (1 Short life span (1

week)week) Form a web Form a web

trapping blood cellstrapping blood cells

Blood Clotting

Break in Capillary Wall

Blood vessels injured.

Clumping of Platelets

Platelets clump at the site and release a protein

Clot Forms

Protein creates a net creating a clot. The clot prevents further loss of blood.

How does Blood Clot?

End of Day 2

Circulatory SystemCirculatory SystemHEARTHEART

Heart Anatomy

Your HeartYour Heart

Pumps blood around Pumps blood around your body to keep your body to keep you alive!you alive!

If your heart stops If your heart stops you will die!you will die!

Heart:Heart:Structure and FunctionStructure and Function

Keeps blood Keeps blood movingmoving

Large organ Large organ composed of composed of – cardiac cardiac

muscle muscle – rich in rich in

mitochondriamitochondria

The Structures of the Heart

Sends Oxygen-Poor blood to the lungs

Receives Oxygen-Poor blood from the body

Vena CavaVein that brings oxygen-poor blood from the body to the heart

Pulmonary VeinsBring oxygen-rich blood from the lungs to the left atrium

Aorta – Artery that supplies the body with Oxygen-Rich Blood

Pulmonary ArteriesBring oxygen-poor blood to the lungs

Sends Oxygen-Rich blood to the body

Gets Oxygen-Rich blood from the Lungs

Pulmonary ArteriesSends Oxygen-Poor blood to the Lungs

Structure of Heart (cont)Structure of Heart (cont) Four chambers Four chambers

– Two upper (Atria)Two upper (Atria) Walls thinnerWalls thinner Less muscularLess muscular

– Two lower Two lower (Ventricles)(Ventricles) Walls thickerWalls thicker More muscularMore muscular Do more workDo more work

Heart Structure Animation

Blood Flow Through the Blood Flow Through the HeartHeart

Bloods Path Through the Bloods Path Through the HeartHeart

Both Atria fill at same timeBoth Atria fill at same time

– Right atrium receives oxygen Right atrium receives oxygen POOR POOR blood from body from blood from body from vena cavasvena cavas

– Left atrium receives oxygen Left atrium receives oxygen RICH RICH blood blood from lungs through from lungs through four pulmonary four pulmonary veinsveins

After filled with blood atria contract, After filled with blood atria contract, pushing blood into ventriclepushing blood into ventricle

Both ventricles contractBoth ventricles contractRight ventricle contracts and Right ventricle contracts and pushes oxygen-poor blood toward pushes oxygen-poor blood toward lungs lungs

through the through the pulmonary arteriespulmonary arteries

Left ventricle contracts and forces Left ventricle contracts and forces oxygen rich blood oxygen rich blood out of heart out of heart Through the aorta (largest vessel)Through the aorta (largest vessel)

Bloods Path Through the HeartBloods Path Through the Heart

The cardiac cycleThe cardiac cycle

Animation of blood flow

Control of the HeartControl of the Heart The Heart is controlled by nerves and The Heart is controlled by nerves and

hormones:hormones:

Nerves:Nerves:– Its own nerves Its own nerves pacemaker which keeps a pacemaker which keeps a

constant beatconstant beat Heart will beat even if it is disconnected from the Heart will beat even if it is disconnected from the

brainbrain Can be substituted by an artificial pacemakerCan be substituted by an artificial pacemaker

- The Brain can speed-up (exercise) or slow down the heart (sleep) if needed

Heart Rate Animation Heart Rate Animation

ECG and (DefibrillationECG and (Defibrillation) ) Paddles Paddles discussion discussion

Control of the HeartControl of the Heart

Hormones:Hormones:

Certain hormones such as Certain hormones such as epinephrine (adrenalin) epinephrine (adrenalin) impact how impact how the heart operates the heart operates

Heart Beat

Control of Heart Rate – Control of Heart Rate – Class DemonstrationClass Demonstration

Resting Heart Rate (beats per min.)

Heart Rate during exercise (beats per min.)

Your Heart: The Vital PumpYour Heart: The Vital Pump

At REST, the heart At REST, the heart beats about beats about 60-80 60-80 times per minute times per minute (~4.7L)(~4.7L)

During EXTREME During EXTREME EXERTION (exercise) EXERTION (exercise) it can beat it can beat between between 150-200 times per 150-200 times per minute (~38L)minute (~38L)

Heart Rate DiscussionHeart Rate Discussion Why??Why??

Brain sends a signal to increase HRBrain sends a signal to increase HR Adrenal Gland secretes epinephrine Adrenal Gland secretes epinephrine Both work together to increase blood flow Both work together to increase blood flow

around the bodyaround the body

– Increased blood flow = Increase OIncreased blood flow = Increase O22/glucose /glucose delivery to cells and COdelivery to cells and CO22 removal removal

DISORDERSDISORDERS

Coronary Artery DiseaseCoronary Artery Disease– Your heart needs Oxygen too!Your heart needs Oxygen too!– Is supplied with Oxygen by coronary arteriesIs supplied with Oxygen by coronary arteries– Coronary arteries can become partially Coronary arteries can become partially

blocked by plaque (fat and cholesterol blocked by plaque (fat and cholesterol mainly)mainly) Causes by lifestyle choice and geneticsCauses by lifestyle choice and genetics

– This block limits the amount of oxygen This block limits the amount of oxygen delivered to the heartdelivered to the heart

– Can cause Can cause tiredness, dizziness and pain tiredness, dizziness and pain

Coronary Artery DiseaseCoronary Artery Disease Can be diagnosed with an Can be diagnosed with an angiogramangiogram

whereby a fluorescent dye is injected into whereby a fluorescent dye is injected into the bloodstream.the bloodstream.

This dye shows up on an x-ray and shows This dye shows up on an x-ray and shows where flow is disruptedwhere flow is disrupted

Disorders (cont)Disorders (cont) Heart AttackHeart Attack

– Coronary Artery(ies) become completely Coronary Artery(ies) become completely blockedblocked No Oxygen can reach the heart muscleNo Oxygen can reach the heart muscle Heart muscle begins to die and eventually stops beatingHeart muscle begins to die and eventually stops beating

SymptomsSymptoms– Nausea, Shortness of breath, Severe chest pain, sweating, Nausea, Shortness of breath, Severe chest pain, sweating,

dizziness, fatiguedizziness, fatigue

IMMEDIATE MEDICAL ATTENTION NECESSARYIMMEDIATE MEDICAL ATTENTION NECESSARY

Heart Attack 1 Heart Attack 2

Disorders (cont)Disorders (cont) StrokeStroke

– Heart attack for the Heart attack for the brainbrain

– Blood cannot reach the Blood cannot reach the brain due to a blockage in brain due to a blockage in its blood vessels or its blood vessels or severe brain bleed.severe brain bleed.

– Brain cells die due to lack Brain cells die due to lack of oxygenof oxygen

– Can lead to paralysis, Can lead to paralysis, loss of ability to speakloss of ability to speak deathdeath

Causes a Stroke?

Current PREVENTION Current PREVENTION RecommendationsRecommendations

Regular exerciseRegular exercise

Weight controlWeight control

Well balanced dietWell balanced diet

Do not smokeDo not smoke

Diet low in saturated fatDiet low in saturated fat

Bill Nye – Blood and Circulation Bill Nye – Blood and Circulation VideoVideo

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