You Gotta HaveYou Gotta Have
The Circulatory SystemThe Circulatory System
Circulatory System Consists Circulatory System Consists of…of…
•Blood Blood VesselsVessels
•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 veins)(arteries, capillaries and veins)
• Arteriestake blood away from the Arteriestake blood away from the heart, veins return blood to the heart, veins return blood to the heartheart
• Blood carries OBlood carries O22 (food) towards (food) towards and COand CO22 (waste) away from (waste) away from tissuestissues
• 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
• Pulmonary CirculationPulmonary Circulation– Carries blood to lungs and Carries blood to lungs and
backback
• Systemic CirculationSystemic Circulation– Carries blood to body and Carries blood to body and
backback
Your Blood Vessels: Your Blood Vessels: Pathway of CirculationPathway of Circulation
• 3 types of vessels3 types of vessels– Arteries(Shown as Red Arteries(Shown as Red
because blood has Obecause blood has O22))– Capillaries(Red and Capillaries(Red and
Blue because some OBlue because some O22 lost to tissues)lost to tissues)
– Veins(Shown as Blue Veins(Shown as Blue because Obecause O22 lost to lost to tissues)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 red deoxygenated 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 are We don’t see arteries because they are
too deep.too deep.• We draw them blue to distinguish them We draw them blue to distinguish them
on diagrams and simplify thingson 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, very elastic and have more muscle.
-Veins are thin walled and contain valves to psh 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, arteries need to be strong!Therefore, arteries need to be strong!
– 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, veins are weakTherefore, veins are weak
Arteries:Arteries:carries blood carries 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 pulse)Steady pulsating (used to measure pulse)ArteriolesArterioles: smaller vessels, enter tissue: smaller vessels, enter tissue
CapillariesCapillaries
– Smallest vesselSmallest vessel– MicroscopicMicroscopic– Walls one cell thickWalls one cell thick– Located at the Located at the
tissuetissue– Nutrients and gases Nutrients and gases
(O(O22, CO, CO22) diffuse ) diffuse herehere
Veins:Veins: Caries blood to the heart Caries blood to the heart
– Carries blood that contains Carries blood that contains waste and COwaste and CO22
• Exception pulmonary veinException pulmonary vein
– Blood under low pressureBlood under low pressure– ValvesValves to prevent back to prevent back
flow due to gravityflow due to gravity
VenulesVenules: small veins, larger : small veins, larger than capillariesthan capillaries
Blood VesselsBlood Vessels
http://www.kscience.co.uk/animations/blood_system.swfAnimation of blood flow
The Aorta – The largest blood The Aorta – The largest blood vesselvessel
http://www.kscience.co.uk/animations/vessels_label.swfBlood Vessel Animation
Circulatory SystemCirculatory System
BLOODBLOOD
The BloodThe Blood
• Body contains 4-6 LBody contains 4-6 L• Consists of Consists of
– WaterWater– Red Blood CellsRed Blood Cells– PlasmaPlasma– White blood cells and White blood cells and
plateletsplatelets
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 blood Leucocytes (WBC - white blood
cells) cells) • Platelets (fragments of the cells in Platelets (fragments of the cells in
bone marrow – no nucleus)bone marrow – no nucleus)• ProteinsProteins• Nutrients - Nutrients - digestive systemdigestive system• Gases - Gases - Respitory systemRespitory system
Oxygen in the BloodOxygen in the Blood
• Hemoglobin , iron Hemoglobin , iron containing moleculecontaining molecule
• 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 tissues– body tissues
O2
O2
O2O2
Carbon Dioxide in the BloodCarbon Dioxide in the Blood
• Hemoglobin also carries COHemoglobin also carries CO22
• COCO2 2 is a waste product of is a waste product of cellular respirationcellular respiration
• 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) + Platelets1% Leukocytes (WBC) + Platelets
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 spleen liver and spleen
Leukocytes (WBC)Leukocytes (WBC)
• WBC fight infectionWBC fight infection– Attack foreign Attack foreign
substancessubstances• Less abundantLess abundant• Created in bone Created in bone
marrow marrow • Some live for monthsSome live for months
– Most just a few daysMost just a few days• Several typesSeveral types• ALL contain nucleiALL contain nuclei• Difference between Difference between
red and white ? red and white ?
PlateletsPlatelets
• PLATELETS are for PLATELETS are for CLOTTING bloodCLOTTING blood
• Cell fragmentsCell fragments• Produced in bone Produced in bone
marrowmarrow• Short life span (1 week)Short life span (1 week)• Form a web trapping Form a web trapping
blood cellsblood 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.
Circulatory SystemCirculatory SystemHEARTHEART
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 movingKeeps blood moving• Large organ Large organ
composed of composed of – Cardiac Muscle Cardiac Muscle – Rich in Rich in
MitochondriaMitochondria
The Structures of the Heart
Right Ventricle
Right Atrium
Left Atrium
Inferior Vena CavaVein that brings oxygen-poor blood from the lower part of the body to the right atrium
Pulmonary VeinsBring oxygen-rich blood from each of the lungs to the left atrium
Superior Vena CavaLarge vein that brings oxygen-poor blood from the upper part of the body to the right atrium
AortaBrings oxygen-rich blood from the left ventricle to the rest of the body
Pulmonary ArteriesBring oxygen-poor blood to the lungs
Left Ventricle
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
http://www.kscience.co.uk/animations/heart_label.swfHeart Structure Animation
Blood Flow Through the Blood Flow Through the HeartHeart
©COPY 1997 HeartPoint©COPY 1997 HeartPoint
Bloods Path Through the Bloods Path Through the HeartHeart
• Both Atria fill at same timeBoth Atria fill at same time
– Rt atrium receives oxygen poor blood from Rt atrium receives oxygen poor blood from body from vena cavasbody from vena cavas
– Left atrium receives oxygen Rich blood Left atrium receives oxygen Rich blood from lungs through four pulmonary veinsfrom lungs through four pulmonary veins
• 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 pushes Right ventricle contracts and pushes
oxygen-poor blood toward lungs oxygen-poor blood toward lungs • through the pulmonary arteriesthrough the pulmonary arteries
Left ventricle contracts and forces Left ventricle contracts and forces oxygen rich blood out of heart oxygen rich blood out of heart • Through Aorta (Largest Vessel)Through Aorta (Largest Vessel)
Bloods Path Through the HeartBloods Path Through the Heart
The cardiac cycleThe cardiac cycle
http://www.kscience.co.uk/animations/blood_system.swfAnimation of blood flow
Control of Heart RateControl of Heart RateResting Heart Rate Heart Rate during exercise
58 80
Control of the HeartControl of the Heart• The Heart is controlled by nerves and hormones:The Heart is controlled by nerves and 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 brainHeart will beat even if it is disconnected from the brain• 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
Control of the HeartControl of the Heart
Hormones:Hormones:
•Certain hormones such as epinephrine Certain hormones such as epinephrine (adrenalin) (adrenalin) impact how the heart impact how the heart operatesoperates
Your Heart: The Vital PumpYour Heart: The Vital Pump
• At REST, the heart At REST, the heart beats about 60-80 beats about 60-80 times per minute times per minute (~4.7L)(~4.7L)
• During EXTREME During EXTREME EXERTION (exercise) EXERTION (exercise) it can beat between it can beat 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 HR Brain sends a signal to increase HR
• Adrenal Gland secretes epinephrineAdrenal Gland secretes epinephrine
• Both work together to increase blood flow Both work together to increase blood flow around the bodyaround the body
• Increased blood frow = increase 02/glucose Increased blood frow = increase 02/glucose delivery to cells and CO2 removaldelivery to cells and CO2 removal
DISORDERSDISORDERS
• Coronary Artery Disease Coronary 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 paintiredness, dizziness and pain
Coronary Artery DiseaseCoronary Artery Disease• Can be diagnosed with an Can be diagnosed with an angiogram angiogram
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 blocked Coronary artery(ies) become completely blocked 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
Disorders (cont)Disorders (cont)• StrokeStroke
– Heart atack for the brain Heart atack for the brain
– Blood cannot reach the Blood cannot reach the brain due to a blockage in brain due to a blockage in its blood vesselsits blood vessels
– 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
Current PREVENTION Current PREVENTION RecommendationsRecommendations
• Regular exerciseRegular exercise• Weight control Weight control • Well balanced dietWell balanced diet• Do not smokeDo not smoke• Diet low in Diet low in
saturated fatsaturated fat
http://www.pbs.org/wgbh/nova/eheart/transplantwave.htmlHeart Transplant Interactive Activity