human circulatory system. circulatory systems open system vs. closed system –both have a pump...
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HUMAN CIRCULATORY HUMAN CIRCULATORY SYSTEMSYSTEM
Circulatory SystemsCirculatory Systems
Open system vs. closed systemOpen system vs. closed system– Both have a pumpBoth have a pump– Open system has no blood vessels to hold Open system has no blood vessels to hold
bloodblood– Closed system has blood contained within Closed system has blood contained within
vesselsvessels
Circulatory systemsCirculatory systems
The simplest of organisms do not have a The simplest of organisms do not have a circulatory systemcirculatory system
Rely on diffusion/osmosis for regulationRely on diffusion/osmosis for regulation
Circulatory systemsCirculatory systems
Other simple organisms rely on the flow of Other simple organisms rely on the flow of water to exchange nutrients and wasteswater to exchange nutrients and wastes
Open vs. Closed Circulatory Open vs. Closed Circulatory systemssystems
Closed circulatory systemsClosed circulatory systems
Vary in complexityVary in complexity
Human HeartHuman Heart
Cardiac muscleCardiac muscle
Structure of the heart wallStructure of the heart wall
Structure of the heart wallStructure of the heart wall
HUMAN CIRCULATORY SYSTEMHUMAN CIRCULATORY SYSTEM
Artery and VeinArtery and Veinstructural comparisonstructural comparison
ArteryArtery
Walls are thickWalls are thick– MuscularMuscular– Elastic, so they can stretch when heart Elastic, so they can stretch when heart
contractscontracts– Must withstand higher pressure than veinsMust withstand higher pressure than veins
AtherosclerosisAtherosclerosis
VeinVein
Thin-walled (less muscle, less elastic Thin-walled (less muscle, less elastic tissue)tissue)
Contain VALVESContain VALVES
to prevent back-flowto prevent back-flow
CapillariesCapillaries
Blood vessels with the smallest diameter Blood vessels with the smallest diameter and thinnest wallsand thinnest walls
Capillary BedsCapillary Beds
Exchange of carbon dioxide, oxygen, and Exchange of carbon dioxide, oxygen, and nutrients occurs in the capillary bedsnutrients occurs in the capillary beds
BLOOD PRESSUREBLOOD PRESSURE
Measurement of both the pressure under Measurement of both the pressure under which the heart contracts (which the heart contracts (systolesystole), as well ), as well as the pressure under which the heart fills as the pressure under which the heart fills ((diastolediastole))
BLOOD PRESSUREBLOOD PRESSURE
Blood pressure is checked in your arm, Blood pressure is checked in your arm, using a using a sphygmomanometersphygmomanometer
Blood PressureBlood Pressure
The pressure generated by your heart can The pressure generated by your heart can be measured in your arm because the be measured in your arm because the pressure is transmitted through the pressure is transmitted through the muscular, elastic arteriesmuscular, elastic arteries
Blood PressureBlood Pressure
Measured in mm HgMeasured in mm Hg
Reported as two numbers:Reported as two numbers:systolic pressuresystolic pressure
diastolic pressurediastolic pressure
Systolic blood pressureSystolic blood pressure
Pressure transmitted when the left Pressure transmitted when the left ventricle contractsventricle contracts– It is the pressure under which the blood is It is the pressure under which the blood is
being forced out of the left ventricle into the being forced out of the left ventricle into the aortaaorta
Diastolic blood pressureDiastolic blood pressure
Is the filling pressure of the heartIs the filling pressure of the heart
Sounds of KorotkoffSounds of Korotkoff
Sounds of KorotkoffSounds of Korotkoff
Sounds of Korotkoff (are caused by Sounds of Korotkoff (are caused by turbulence in arterial blood flow.turbulence in arterial blood flow.– A well-trained examiner can hear 5 different A well-trained examiner can hear 5 different
Korotkoff sounds, which vary slightly in qualityKorotkoff sounds, which vary slightly in quality– The first and fifth Korotkoff sounds are used The first and fifth Korotkoff sounds are used
to define blood pressureto define blood pressure
Pulse PointsPulse Points
Blood PressureBlood Pressure
Generally measured over Generally measured over
the brachial arterythe brachial artery
Why is blood pressure important?Why is blood pressure important?
Blood pressure must remain in a normal Blood pressure must remain in a normal range so that tissues can receive range so that tissues can receive adequate blood flow in order to exchange adequate blood flow in order to exchange gases, nutrients, and wastes efficientlygases, nutrients, and wastes efficiently
HYPERTENSIONHYPERTENSION
Elevation in blood pressureElevation in blood pressure
Fairly common: about 30%Fairly common: about 30%– almost 1 in 3 adults!almost 1 in 3 adults!
HTN more common in HTN more common in – African AmericansAfrican Americans– Obese peopleObese people
HypertensionHypertension
High blood pressure can damage the heart High blood pressure can damage the heart and blood vesselsand blood vessels
Increases the chances of having a strokeIncreases the chances of having a stroke
Cause is multi-factorialCause is multi-factorial
Can be treated with medication; Can be treated with medication; sometimes with diet and exercise alonesometimes with diet and exercise alone
Regulation of blood pressureRegulation of blood pressure
Conduction System of the HeartConduction System of the Heart
ElectrocardiogramElectrocardiogram
Useful tool for studying the conduction of Useful tool for studying the conduction of impulses through the heartimpulses through the heart
ElectrocardiogramElectrocardiogram
P wave represents depolarization of the P wave represents depolarization of the atriumatrium
QRS complex represents depolarization of QRS complex represents depolarization of the ventriclesthe ventricles
T wave represents repolarization T wave represents repolarization (“recharging” for the next beat(“recharging” for the next beat
Normal ElectrocardiogramNormal Electrocardiogram
ECG abnormalitiesECG abnormalities
After a myocardial infarction (heart attack, After a myocardial infarction (heart attack, “MI”), the damaged areas of the heart no “MI”), the damaged areas of the heart no longer have normal conduction of longer have normal conduction of impulsesimpulses– Results in a change in the normal waveformsResults in a change in the normal waveforms
ECG abnormalitiesECG abnormalities
ECG abnormalitiesECG abnormalities
ECG abnormalitiesECG abnormalities
Atrial fibrillationAtrial fibrillation
ECG abnormalitiesECG abnormalities
Acute myocardial infarction (heart attack)Acute myocardial infarction (heart attack)
COMPOSITION OF BLOODCOMPOSITION OF BLOOD
Blood is made up of a fluid portion and a Blood is made up of a fluid portion and a cellular portioncellular portion
PLASMAPLASMA
Made up of water, proteins, ions, amino Made up of water, proteins, ions, amino acids, sugarsacids, sugars
Carries carbon dioxide (released from Carries carbon dioxide (released from tissues)tissues)
Carries nutrients from the digestive Carries nutrients from the digestive system, hormonessystem, hormones
Cells in the BloodCells in the Blood
Erythrocytes: Red Blood Cells, RBC’sErythrocytes: Red Blood Cells, RBC’s
ErythrocytesErythrocytes
Contain hemoglobinContain hemoglobin– A proteinA protein– Transports OxygenTransports Oxygen
ErythrocytesErythrocytes
Hemoglobin structureHemoglobin structure
ErythrocytesErythrocytes
Live about 120 daysLive about 120 days
Produced in the bone marrowProduced in the bone marrow
Productions is regulated by a hormone Productions is regulated by a hormone from the kidneys-from the kidneys-– erythropoetinerythropoetin
Blood CellsBlood Cells
Leukocytes = White Blood CellsLeukocytes = White Blood Cells– Function in the immune systemFunction in the immune system– Form a second line of defense against Form a second line of defense against
bacteria and virusesbacteria and viruses– Larger than RBC’sLarger than RBC’s
LeukocytesLeukocytes
GranulocytesGranulocytes– NeutrophilsNeutrophils– BasophilsBasophils– EosinophilsEosinophils
LymphocytesLymphocytes
MacrophagesMacrophages
GranulocytesGranulocytes
NeutrophilNeutrophil– Greatest in numberGreatest in number– Has a segmented nucleusHas a segmented nucleus– Functions in bacterial infectionsFunctions in bacterial infections– Short-livedShort-lived
NeutrophilsNeutrophils
BasophilBasophil
Also a granulocyteAlso a granulocyte
Very few in numberVery few in number
Function is not completely understoodFunction is not completely understood
Contain granules that are important in Contain granules that are important in immune responseimmune response
EosinophilEosinophil
Granulocyte containing very large Granulocyte containing very large granulesgranules
Important in allergiesImportant in allergies
Few in number (far less than neutrophils Few in number (far less than neutrophils but more than basophils)but more than basophils)
EosinophilEosinophil
LymphocytesLymphocytes
Important in immune systemImportant in immune system– Making of antibodiesMaking of antibodies– Fighting viral infectionsFighting viral infections
Has a large, dark-staining nucleusHas a large, dark-staining nucleus
LymphocyteLymphocyte
MacrophagesMacrophages
Phagocytes: engulf and destroy cellular Phagocytes: engulf and destroy cellular debris and bacteria/virusesdebris and bacteria/viruses
Lifespan is months to yearsLifespan is months to years
Larger than a lymphocyteLarger than a lymphocyte
MacrophageMacrophage
Other Blood ComponentsOther Blood Components
PlateletsPlatelets– Involved in blood coagulation (clotting)Involved in blood coagulation (clotting)– Sticky; form a plug at the site of bleedingSticky; form a plug at the site of bleeding– Small and numerousSmall and numerous
Blood clotting is a very complex processBlood clotting is a very complex process– Involves many proteins (factors)Involves many proteins (factors)– Cascade eventCascade event
PlateletsPlatelets
PlateletsPlatelets
What protein forms the “threads” that trap What protein forms the “threads” that trap the platelets when forming a clot??the platelets when forming a clot??
Blood disordersBlood disorders
ANEMIA: qualitative or quantitative ANEMIA: qualitative or quantitative reduction in hemoglobinreduction in hemoglobin– Most common is iron deficiency anemiaMost common is iron deficiency anemia
Caused by low levels of iron: causes may be Caused by low levels of iron: causes may be dietary, chronic blood loss from gutdietary, chronic blood loss from gut
– Vitamin B6, folic acid deficienciesVitamin B6, folic acid deficiencies– Aplastic anemiaAplastic anemia
HemoglobinHemoglobin
Iron Deficiency AnemiaIron Deficiency Anemia
Iron Deficiency anemiaIron Deficiency anemia
Unusual symptomsUnusual symptoms– GlossitisGlossitis– Pica: geophagia (compulsive eating of dirt), Pica: geophagia (compulsive eating of dirt),
pagophagia (compulsive eating of ice)pagophagia (compulsive eating of ice)
Iron Deficiency anemiaIron Deficiency anemia
Blood smearBlood smear
Iron Deficiency anemia: Iron Deficiency anemia: treatmenttreatment
Treatment depends on the causeTreatment depends on the cause– Iron supplementIron supplement– Dietary changesDietary changes– In severe cases, blood transfusionIn severe cases, blood transfusion
Sickle Cell anemiaSickle Cell anemia
Inheritable disorder (co-dominance)Inheritable disorder (co-dominance)– Mutation in the hemoglobin molecule (HgbS)Mutation in the hemoglobin molecule (HgbS)– RBC’s form a sickle shapeRBC’s form a sickle shape– Reduces oxygen carrying capacity of the Reduces oxygen carrying capacity of the
bloodblood– African descentAfrican descent– Confers resistance to malariaConfers resistance to malaria
Sickle Cell anemiaSickle Cell anemia
Sickle Cell CrisisSickle Cell Crisis
Caused by a variety of things: stress, Caused by a variety of things: stress, fever, illness, alcohol & drug use, fever, illness, alcohol & drug use, dehydrationdehydration
Causes severe pain in tissues, bones, Causes severe pain in tissues, bones, jointsjoints
Can be life-threateningCan be life-threatening
Sickle Cell CrisisSickle Cell Crisis
Symptoms due to sickle cells blocking Symptoms due to sickle cells blocking capillary flowcapillary flow
Treatment: fluids, pain medicine, other Treatment: fluids, pain medicine, other treatments for specific problems (i.e. heart treatments for specific problems (i.e. heart attack, stroke, blindness)attack, stroke, blindness)