cardiovascular system (circulatory system). blood from the body deoxygenated blood enters the right...
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Cardiovascular System(Circulatory (Circulatory
System)System)
Blood From the BodyDeoxygenated blood enters the RIGHT ATRIUM
from the VENA CAVA
Atrium Contracts forcing the blood through the TRICUSPID VALVE
Into the RIGHT VENTRICLE
Ventricle contracts pushing blood through SEMILUNAR VALVE
Blood flows through either the RIGHT or LEFT PUMONARY ARTERY
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A heartbeat is a two-part pumping action that takes about a second. As blood collects in the upper chambers (the right and left atria), the heart's natural pacemaker (the SA node) sends out an electrical signal that causes the atria to contract. This contraction pushes blood through the tricuspid and mitral valves into the resting lower chambers (the right and left ventricles). This part of the two-part pumping phase (the longer of the two) is called diastole.The second part of the pumping phase begins when the ventricles are full of blood. The electrical signals from the SA node travel along a pathway of cells to the ventricles, causing them to contract. This is called systole. As the tricuspid and mitral valves shut tight to prevent a back flow of blood, the pulmonary and aortic valves are pushed open. While blood is pushed from the right ventricle into the lungs to pick up oxygen, oxygen-rich blood flows from the left ventricle to the heart and other parts of the body.After blood moves into the pulmonary artery and the aorta, the ventricles relax, and the pulmonary and aortic valves close. The lower pressure in the ventricles causes the tricuspid and mitral valves to open, and the cycle begins again. This series of contractions is repeated over and over again, increasing during times of exertion and decreasing while you are at rest. The heart normally beats about 60 to 80 times a minute when you are at rest, but this can vary. As you get older, your resting heart rate rises. Also, it is usually lower in people who are physically fit.
Blood Enters the LungsEnters the Lung (either right or left lung)
Blood is deoxygenated
Oxygenation is accomplished in the air sacs of the lungs at the same time the CO2 is being expelled
Oxygenated Blood is returned to heart via RIGHT or Left Pulmonary Vein. This is the only place where a vein carries oxygenated blood
Oxygenated Blood from the Lungs
Enter the LEFT ATRIUM which contracts
Blood is pushed through the BICUSPID Valve
Blood enters the Left Ventricle
Ventricle acts as the pump for the newly oxygenated blood
Blood is sent through the AORTIC SEMILUNAR VALVE
Blood then flows from the heart via the AORTA
Coronary Circulation
Myocardium must have blood to sustain is pumping
Right and Left Coronary arteries branch off the AORTA just above the heart
Branches of these arteries encircle the heart muscle delivering O2 and nutrients
Deoxygenated blood from these arteries return via CORONARY VEINS to RIGHT ATRIUM
Deoxygenated blood enters the atrium via the CORONARY SINUS
Systemic CirculationOxygenated
blood leaves the heart via the AORTA
As it leaves the anterior portion of the heart it forms the AORTIC ARCH
Circulation to Head
Arteries of the Head and Upper Torso
Ascending AortaAORTIC ARCH branches into 3 Main arteries
carry blood to arms, neck and head
Left Common Carotid Artery Brachiocephalic Artery – Right Common
Carotid, Right SubclavianLeft Subclavian Artery – left axillary, left
brachial
Descending Aorta
Coronary Artery – feeding the heartMore Branches feeding the body wall,
stomach, intestines, liver, etc.THORACIC AORTAABDOMINAL AORTAETC.
Types of Vessels
Arteries carry oxygenated blood away from
the heart (one exception)
Types of Vessels
BLOOD FLOW THROUGH VESSELS - Arteries
Transport blood under high pressure
Walls are elastic, muscular and thick
3 layers from interior to exterior
Tunica interna, media, and externa
Arteries branch into arterioles
Arterioles give rise to capillaries
Capillaries
Types of Vessels
CapillariesSmallest of blood vessels – microscopicConnect arterioles to venulesWalls thin to allow selective permeability of
various cells and substances – Nutrients and O2 pass out to surrounding tissueWaste CO2 and metabolic waste may enter to be
excreted Tiny opens allow WBC to leave the bloodstream
and enter tissue to help destroy invading bacteriaPlasma;a diffuses out of the bloodstream and into
tissue spaces (interstitial fluid) that is returned to the bloodstream in the form of lymph via lymph vessels
Diameter so small RBC “march” single file
VeinsCarry deoxygenated
blood and other waste products for
excretion
Types of Vessels
VeinsVeins similar is size to arteriesLess elastic and muscularWalls much thinner – blood pressure lowerThin walls – will collapse easily when not filled with
bloodContain one – way valves – prevent reflux or back
flow of bloodMore valves in lower extremities because of gravitySkeletal muscle also assist in Venous returnVenous blood returns to the heart via the Superior
and Inferior Vena Cava
Blood Pressure
Heart Pumps Blood into ArteriesSurge creates pressure on artery walls Pressure at the moment of ventricular
contraction is the systolic pressureAverage Systolic Pressure 120 mm/HgLessened pressure at ventricular
relaxation is diastolic pressureAverage Diastolic Pressure 80mm/Hg
120/80
BLOOD PRESSURE DISORDERS
Hypertension – “High Blood” – When BP is constantly greater than 140/90
Sometimes called the SILENT KILLERLeads to strokes, heart disease and kidney
failureTreated with diet, medication and weight loss 1 out of 5 American have hypertension
Hypotension – “Low Blood” – When Systolic BP is constantly lower than 100mm/Hg
Treated with fluids, medication
Disorders of Blood VesselsAneurysm – ballooning out of an artery –
thinning wall and weakening of the blood vessel
Sometimes pain and pressure sometimes no symptoms
Sometime surgically correctedRupture can be life threatening if in brain
or a large vessel like abdominal aorta
ArteriosclerosisArtery walls thicken – loss of elasticity
usually due to old ageNarrowing of artery – interfering with blood
supplyCan cause hypertension or cardiac infarct
AtherosclerosisDeposits of fatty substances form along the
walls of the arteries Narrowing of artery – interfering with
blood supplyCan cause hypertension or cardiac infarct
GangreneDeath of body tissue due to insufficient
blood supply caused by disease (diabetes) or injury
Pain and darkening skin and underlying tissue
Attempt to treat with antibioticsUsually must amputate affected area
PhlebitisInflammation of the lining of a vein,
accompanied by clotting of blood in the vein
Symptoms can include edema, pain and redness
Treat with medication, elevation and elastic stockings
EmbolismTraveling blood clotPulmonary embolism is clot in lung that can
cause respiratory arrest
Varicose VeinsSwollen veins resulting
from slowing down of blood flow back to heart
Blood backs up; distending the vein and valves
Usually caused by hereditary weakness
Age and pregnancy
HemorrhoidsVaricose veins in the walls of the lower
rectum and the tissues around the anus
Cerebral hemorrhageBleeding from blood vessels with the brainCan be caused by arteriosclerosis, disease,
aneurysm, or injuryCan cause permanent damage to brain
tissue and/or death
Peripheral Vascular DiseaseBlockage of arteries usually in legs
Symptoms – pain and cramping in the legs or buttocks while walking – claudicating
Must be treated or can progress where amputation is necessary
Treatments: medication, diet
Transient Ischemic Attacks (TIA)
Temporary interruption of the blood flow (ischemia) to the brain or part of the brain
Can be caused by narrowing of carotid artery
Symptoms include dizziness, weakness or temporary paralysis
Cerebral Vascular Accident (CVA) Stroke
Sudden interruption of blood supply to the brain
Loss of O2 to brain causing impairment of the brain tissue and/or death
3rd leading cause of death in USRisk factors include smoking, hypertension,
heart disease and family HX90% are caused by blood clots10% by bleeding into brain when vessel
ruptures
TYPES OF STROKE
ISCHAEMIC STROKE
HAEMORRHAGIC STROKE
Conduction of the HeartCardiac Cycle – one complete heart beat
Conduction System of the HeartHeart Rate (HR)
Heart must contract rhythmically
Each cycle or beat is about 0.8 seconds
Average rate of heart in an adult is 72-75 beats/min
Tachycardia – fast rate – usually over 100
Bradycardia – slow rate – usually under 60
SA Node – Pacemaker of the Heart
Conduction System initiates beats in intrinsic by distributing electrical impulses
Begins with the SA (Sinoatrial) node
Located in the superior wall of right atrium
Send the beginning of the electrical impulse over both atria causing them to contract simultaneously
Causes blood to flow downward from upper atrial chamber to AV opening
Bicuspid and Tricuspid valves open
Conduction System Semilunar valves closed at this time - no
blood to enter the pulmonary artery or aorta
Ventricles will relax at this time allowing them to fill with blood
Brief pause to allow atria time to complete contraction
Depolarizes the AV (atrioventricular) node
AV Node Located in the lower portion of the right atrium
AV node stimulates contraction of both ventricles
Contraction start at the apex and moves toward the atria
Send impulse down Bundle of His through the ventricular septum
Bundle divides in right and left branch that further subdivide sending messages up the ventricular walls by way of the Purkinje fiber network
Semilunar valves open allowing blood to move into the lungs via the pulmonary artery and out to body via aorta
Atrium then relax and AV valves close
Cycle continuesVentricles relax
Semilunar valves closed to prevent the blood flowing back in to the ventricles
SA Node signals again
Electricity gone haywire
Conduction Defects
Conduction AbnormalitiesHeart Block – AV damage – SA impulse
doesn’t reach ventricle – ventricles will beat at their own rate – slower
Damage to SA node – slower heart rate – sometimes need artificial pacemaker – defibrillation or “shocking” patient
Ischemia can lead to Fibrillation – rapid uncoordinated shuddering of heart muscle
Cardiac arrest – stopping of conduction
Autonomic Nervous System
Neural Control
Autonomic Nervous SystemHeart enervated by autonomic nervous
system – controls speed of contractions
Sympathetic NS will speed it up temporarily In times of physical or emotional stress Will increase availability of O2 and glucose
to cells
Parasympathetic NS will slow it temporarilyPrimarily the vagus nerve
Hormones and IonsHormone Thyroxine and epinephrine can also
increase heart rate
IonsLow calcium – depresses the heartToo much calcium can stop the heartLow K+ causes feeble or abnormal
beatingLow Na+ depress heart
Other FactorsAge- faster in babies – gradually decreases
through out life in normal heart
Gender – faster in females
Temperature – fever and exercise increase HR due to increase in metabolic rates; cold decreases HR
Medication – chemically stimulating or decreasing heart; intentional or side affect
Diet – digestion increase HR
Cardiac Cycle Mid to late Diastole
We will begin with the heart at complete relaxation
Pressure in heart is lowBlood flowing passively into atrium from the
pulmonary and systemic systemsSemilunar valves closed AV valves openAtria contract and force blood into ventricles
Cardiac Cycle Ventricular Systole
Shortly the ventricles will begin to contract and pressure increases rapidly
Pressure closes AV valves
When intraventricular pressure higher than in large vessels leaving heart - semilunar valves open
Blood rushes out of ventricles to vessels
Atria will be relaxed at this time and their chambers are filling
Cardiac CycleEarly Diastole At the end of Systole ventricles relax
Semilunar valves snap shut – preventing black flow
Intraventricular pressure drops
AV valves forced open
Ventricles beginning to refill rapidly
Cycle complete
Cardiac CycleNormally atria contract simultaneously as the
ventricles relax
Ventricles contract while atria relax
Diastole – phase of relaxation
Systole – phase of contraction
One cycle consists of systole and diastole of both atria and the systole and diastole of both ventricles
Timing Cycle lasts 0.8 seconds
First 0.1 seconds, the atria contract and ventricles relax
0.3 seconds atria are relaxing and ventricles contracting
Last 0.4 seconds is quiescent period – all chambers in diastole – heart resting
Heart SoundsFirst sound – Lub – is closing of the AV
valves – louder and stronger sound
Second sound – dup – closing of the semilunar valves at the end of systole – sound tends to be short and sharp
Pause
Heard with stethoscope
Heart MurmursAbnormal or unusual heart sounds
Blood flow silent unless strikes obstruction
Fairly common in children and elderly
Usually indicate valve problems
Medication can help some
Surgery required in severe cases
Blood Pressure
Pressure exerted at moment of contraction of ventricles – Systolic Blood Pressure – top number
Lessened force of the blood when ventricles relax – Diastolic Blood Pressure – bottom number
Pressure highest in the arteries close to initial surge of blood and gradually decreases as it it travels further from heart
Average BP in adult is 120mmHg/80mmHg
Directly related to CO and peripheral resistance
Blood PressurePeripheral Resistance – amount of friction
encountered by the blood as it flows through the blood vessels
Increase by constriction of blood vessels-by SNS or atherosclerosis
Increased by increased blood volume or blood viscosity
Blood PressureANS – sympathetic division causes vasoconstriction
Loss of blood
Gravity after sitting or laying down and rising suddenly
Exercise – vasoconstriction except in muscles vasodilatation
Never cause vasoconstriction of blood vessels in heart or brain
Blood Pressure
Kidneys – alters blood volume
Increases liquids excretion when BP goes up – decrease blood volume – decrease BP
Temperature – cold causes vasoconstriction
Chemicals
Epinephrine – increase HR – increases BP
Nicotine – increases HR – increases vasoconstriction - Increases BP
Alcohol – vasodilator – decrease BP
Blood Pressure DisordersHypotension – low BP
Systolic below 100
Usually no cause for concern under normal circumstances
Orthostatic hypotension – postural changes – increase with old age
Chronic Low BP can indicate poor nutrition and inadequate levels of blood proteins
Circulatory Shock- not enough blood volume in vessels
Blood Pressure DisordersHypertension – high blood pressure
Pathologic – sustained BP of 140/90 or higher
People can be asymptomatic for first 10-20 years – slowly causing unknown damage – silent killer
Increase resistance causes heart to work harder – over stretching the heart muscle
Can be affected by diet, obesity, heredity, race and stress
Pulse Pulse throbs at pressure points throughout body
Alternating expansion and contraction of an artery as blood flows through it
Brachial- near crook of elbow
Common carotid – neck
Dorsalis pedis – anterior foot
Temporal – temples on sides of face
Radial - wrist
Femoral – groin
Popliteal – behind knee Posterior tibial - ankle
Cardiac Output - COAmount of blood pumped out of each side of the heart in
one minute
Product of the heart rate (HR) and the stroke volume (SV)
CO = HR X SV
Stoke Volume is amount of blood pumped out of ventricles with each contraction
Normal CO = HR (75b/m) X SV (70 ml/beat)CO = 75 X 70CO = 5250 ml/min
Cardiac OutputAverage adult has 5000 ml of blood in the
entire system
Entire volume of blood passes through the heart (therefore through the body) in 1 minute
Cardiac Output will vary with demands
Increase with increase volume
Increases with increased rate
Cardiac OutputStroke Volume – volume of blood pumped
from the ventricles with each contraction
Healthy heart pumps 60% of the blood that enters it – 70 ml or 2 ounces – with each contraction
CO – Starling’s Law of the Heart
SV controlled by how much the cardiac muscle cells are stretched just before they contract
Increased stretching = stronger contraction
Amount of stretching affected by venous return- amount of blood entering
Stroke Volume Things that affects it
Slow heart rate allows more time for filling and stretching
Strong contracting of skeletal muscles affecting venous return – exercise
Rapid heart rate decreases filling time
Severe blood loss lowers venous return
Cardiac muscle weakening or damage decrease SV
Heart will try to maintain CO by increasing HR
Pumping Efficiency ProblemsCongestive Heart Failure – efficiency is decreased so
that circulation is inadequate to meet tissue demands
Usually progressive
Weakening of heart muscle due to MI, arteriosclerosis or persistent hypertension
Pulmonary congestion occurs when left heart fails – can lead to pulmonary edema
Peripheral congestion when right side fails
If one side fails more stress to other side can lead to total heart failure
Cardiovascular Disease
Disease of the Heart
Infections/InflammationsPericarditis Infection in the pericardium – the outer layer of
the heartSymptoms include pain, cough, dyspnea, rapid
pulse and fever
MyocarditisTreated with medications Inflammation of the cardiac muscleSymptoms and treatment same as pericarditis
Infections/InflammationsEndocarditis Inflammation of membrane lining the heart
and covering valvesCan lead to blood clot Can lead to valve difficulties
Rheumatic Heart Disease Antibodies fighting rheumatic fever or strep
throat can attack the valves and the lining of the heart
Can cause valves to stop closing properly
Coronary Artery DiseaseAngina pectoris
Severe chest pain caused by not enough O2 to heart myocardium
Not a disease but symptoms of narrowing of coronary arteries
Treat with medication – nitroglycerine – to dilate arteries
Secondary with by-pass surgery
Myocardial InfarctionMI or Heart attack – lack of blood supply to heart
muscle causing death of tissue
Can be caused by narrowing of arteries or blood clot
Amount of damage will determine mortality and/or resulting long term problems
Prevention is the best treatment
After damage done- medication can strengthen contraction and or dissolve clots
Invasive Treatment
Cardiac Surgery
Angioplasty“balloon surgery”
Small deflated balloon threaded into coronary artery to reach blockage
Balloon inflated to push blockage against artery wall
Balloon deflated and removed
If doesn’t work by-pass surgery may be needed
StintsSmall device threaded
into coronary arty to try to hold the vessel open after successful angioplasty
Not always successful long term
Tries to prevent Heart Attacks or MI from reoccurring
Coronary Artery By-PassSurgery to detour or by pass the blockage
in a coronary artery
Healthy blood vessel used
Not as successful in increasing longevity as once thought
Heart TransplantsIndividual’s heart can no longer function
properly
Due to damage or disease or in some congenital heart defect
Must “match” body tissue to prevent rejection by the recipient's own body
Donor must “die” for someone needs a transplant
Artificial HeartsLast ditch effort
Used only for short periods of time until a donor heart can be found
Pacemaker and Implantable DefibrillatorPacemaker to take over the work of the SA
node
Defibrillator – implanted to shock heart back into a regular rhythm – for those at risk or have a history of ventricular tachycardia
The River of Life
Blood
BloodSpecialized connective
tissuePumped by the heartCarried by the blood
vesselsComposed of:Blood cellsPlasmaPlatelets
BloodTransports O2 to cells for metabolismTransports CO2 back to lungsCarries nutrients, ions and water from the digestive
tract to all cellsTransports waste for cells to sweat glands and kidneys
for excretionTransports hormones from endocrine glands to target
organsTransports enzymes to cells to regulate chemical
processes and chemical reactionsHelps regulate pH through buffers and amino acidsHelps regulate body temperature by helping to regulate
H2O content of cells through Na ions (osmosis)Clotting mechanism helps prevent fluid lossHelps protect the body from foreign microorganisms
and toxins
Blood Cells - Erythrocytes Red Blood cells – contain no nucleus 95% of blood volume Hematopoiesis – formation – in red bone
marrow Come from stem cells – live for about 120
days Appear as biconcave discs- edges thicker
than center Composed of:1. Protein (stoma& cytoplasm)2. Lipids including cholesterol3. Hemoglobin
Erythrocytes - HemoglobinCombine with O2 in the lungs and transport it to
various tissuesCombine with CO2 in tissues and transport it to
the lungs for expulsion Hemoglobin is a protein – globin and a pigment –
hemeHeme combines with O2 – Globin combines with
CO2Normal Hemoglobin blood level is 4.8 million
RBCS/mm3 in women to 5.4 in men
Blood Cells - LeukocytesWhite Blood CellsContain no pigment and have a nucleusGeneral function – combat inflammation and
infectionLarger than RBCHave ability to leave blood and move into
tissue 5000 – 90000/mm3Live only a few days normally but only a few
hours during an infection2 sub categories – granular and non-granular
Leukocytes - GranularNeutrophils – most common leukocytesMost active Move into cells and phagocytize (consume)
foreign substances and secrete lysozyme which helps destroy certain bacteria
Pus consists of dell debris, fluid and dead neutrophils
Leukocytes - GranularEosinophils – combat irritants, such as pollen
that cause allergiesProduce antihistaminesAlso can attack some worm parasites
Leukocytes - GranularBasophiles – combat irritantsRelease heparin (an anticoagulant)
histamine (an inflammatory substance) and serotonin (vasoconstrictor) into the tissues
Leukocytes – Non - GranularMonocytes – phagocytoticLargest leukocytesWhen they leave the blood they increase in
sizePhagocytize bacteria, dead cells and/or
cellular debris
Non GranularLymphocytes – involved in production of
antibodiesPlay a crucial role in the immune system’s
responseSmallest of leukocytesInvolved in controlling cancer cells,
destroying microorganisms and rejecting foreign tissue implants
Blood Cells - ThrombocytesPlatelets
Disc shaped cellular fragments with a nucleus
Prevent fluid loss when blood vessels are damaged by clotting
Life span about 1 week
Produced by red bone marrow
PlasmaFluid part of the blood
91% of plasma is water
7% proteins- albumin and fibrinogen and globulins
Rest is solutes such as ions, nutrients, waste products, gases, enzymes and hormones
Albumin
Initiates osmotic pressure
Helps control water balance between blood and tissues
Plasma Proteins - Globulins
Some act as transport molecules for hormones and carry them to target organs
Some are antibodies – important in the immune system
Plasma Proteins - FibrinogenVital in blood clotting
Clotting of the BloodCoagulation –
the process of the clotting of the blood
Must occur to stop bleeding
Unnecessary clotting can clog a vessel
Clotting of the BloodVessel damage – leakage occursThromboplasin produced (needs Vit K) As blood platelets flow over the roughened area
they disintegrate, releasing thromboplasinThromboplasin + Ca = ThrombinThrombin + fibrinogen = fibrinFibrin are gel-like threads that layer themselves
over the cut, creating meshlike networkNetwork traps RBC, platalets and plasma
creating a blood clotSerum oozes out of the cut – slowly drying
creating a crust (scab) over the treadsClotting time is 5-15 min in adults
Blood Types4 major types – A, B, AB and OBlood type is inheritedDetermined by the presence or absence
of the blood glyoprotein called antigen located on the surface of the RBC
A has A antigenB has B antigenAB has bothO has neither
Blood Groups - AntibodiesProtein in the plasma
called antibody
A has “b” antibodies
B has “a” antibodies
AB has no antibodies
O has both
Blood TypesImportant to know type when receiving
transfusionAntibodies can react with antigens of
the same type – clumping of blood cellsA must receive A or O bloodB must receive B or O bloodAB can receive all typesO can donate to all types (universal
donor)
Rh factorAntigen found on the surface of the RBC
If someone has it they say they are Rh+
If someone does not have it Rh-
Important to know in transfusions
Important to know if Mother is Rh- and unborn baby is Rh+
Blood Disorders
Blood types
Blood Disorders - HemophiliaHereditary disorder
Blood clots slowly or abnormally
Only in males
Can be treated with clotting factors
Avoid trauma
Blood Disorders - LeukemiaCancerous or malignant condition
Abnormally high production of WBC that do not fight infection
Displace the normal # of RBC- thus interfering with amount of O2 circulating in the blood
Treatment – radiation, and/or chemotherapy
Blood Disorders - AnemiaDeficiency of RBC and amount of hemoglobin
Varying degree of dyspnea, pallor, palpitations and fatigue
Can be caused by bleeding or extreme destruction of malformation of RBC
Types: Pernicious – Vit B-12 deficiencyAplastic – bone marrow doesn’t produce enough
RBC and WBC
Sickle Cell DiseaseChronic disease inherited
from both parents
RBC form in crescent shapes that carry less O2
Almost exclusively in blacks
Treatment drugs and transfusions
Sickle Cell Trait is when only one parent is affected
Blood Disorders - SepticemiaPresence of a pathogen or toxin in the blood
Blood infection Treated with antibiotics
Can cause death if untreated or not treated quickly enough
Blood Disorders - Thalassemia
Also called Cooley’s anemia
Defect in RBC formation
Fatigue, enlarged spleen, bone deformaties
Medication and transfusions
Affects blacks and Mediteranian descent
Blood Disorders - MalariaInfectious diseaseCaused by protozoan
parasiteTropical climates – by
mosquitoCause symptoms of
anemia, tachycardia, fever, chills, nausea flu like symptoms, and coma and death
Blood Disorders - Mononucleosis
Mono – Kissing Disease – Glandular FeverCaused by Epstein Barr Virus (EBV)Symptoms fever, malaise, sore throat, enlarged glandsIncrease number of WBC - lymphocytes Spread by person-to-person contact Saliva is the primary method of transmitting Coughing or sneezing, causing small droplets of
infected saliva and/or mucus to be suspended in the air which can be inhaled by others.
Sharing food or beverages from the same container or utensil
Can lead to liver damage or spleen rupture
Interaction with Other Body Systems
IntegumentaryBlood flows to the skin to aid in the temperature
control for the body
Blood flow to skin brings O2 and nutrients to and are moves wastes from skin and glands
Dilation of vessels in the dermis occurs when we are embarrassed; resulting in “blushing”
Skin absorbs sunlight to indirectly allow for the production of Ca needed in muscular contraction of the heart
Muscular SystemExercising muscles receive increase blood flow
delivering O2 and nutrients and removing wastes
Cardiac and smooth muscles contractions maintain blood flow and blood pressure
Exercise helps prevent cardiovascular disease
Diaphragm contraction allows breathing sending O2 to lung for blood to pick it up for delivery to body
Heart is a muscle
Blood delivers O2 and nutrients for health and function of muscles and connective tissues
Skeletal SystemBones store and release calcium to maintain blood
levels – cardiac muscle needs Ca to contract
Bones are site of hematopoisesis
Bones (sternum and ribs) protect the heart
Long bones protect important arteries
Blood provides O2 and nutrients for health and function of the bones and removal of wastes
Nervous SystemBrain and spinal cord depend on blood flow
for survival
ANS regulates heartbeat and blood pressure
Pain felt in “heart attacks” help send signals to the person that they need to seek medical attention
Blood flow aids in waste removal from nervous system cells
Respiratory SystemRespiratory system provides the
exchange of O2 and CO2 with the red blood cells
Respiratory movements aid in venous blood return to heart
Heart provides the O2 and nutrients for health of the respiratory cells and for waste removal
Digestive SystemDigestive system breaks down food and
nutrients into forms that can be absorbed and transported in the blood stream
Iron and B vitamins are provided by the digestive system for red blood cell formation
Heart provides the O2 needed to maintain digestive function and metabolism and for waste removal
Reproductive SystemIncreased blood volume allows penis to maintain
erection
Increased blood volume during sexual arousal in both sexes allow sexual “readiness”
Estrogen helps maintain vascular health in females
Blood provides O2 and nutrients for health and function of reproductive organs and for waste removal
Excretory SystemKidneys filter the blood of wastes and excess
electrolytes and water
Kidneys help control blood volume and blood pressure
Blood pressure helps maintain kidney function
Blood provides nutrients and O2 for cells of the excretory system and for waste removal
Endocrine SystemBlood stream transports hormones to
target sites
Epinephrine , thyroxin and antidiuretic hormones effect blood pressure
Epinephrine , thyroxin effect heart rate
Blood supplies O2 and nutrients for health and function of endocrine glands and for waste removal