human circulation ib master 2016
TRANSCRIPT
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Transport - Transport - TheThe
CardiovascularCardiovascularSystemSystem
Essential IdeaEssential Idea The blood system The blood system
continuously transports continuously transports substances to cells and substances to cells and simultaneously transports simultaneously transports waste products away from waste products away from cells. cells.
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
General Functions ofGeneral Functions of TransportTransport SystemsSystems......
Maintain internal homeostasisMaintain internal homeostasis Deliver oxygen, nutrients, Deliver oxygen, nutrients,
hormoneshormones Remove CORemove CO22 and other metabolic and other metabolic
wastes (urea)wastes (urea) Maintain cells in a fluid Maintain cells in a fluid
environment that allows exchange environment that allows exchange of these many materialsof these many materials
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Blood Blood VesselsVessels
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Arteries are adapted to deal with blood under HIGH
pressureThick outer wall
Thick layer of muscle and elastic fibres
Narrow lumen(space through which blood flows)
Veins are adapted to deal with blood under LOW
pressure
Wide lumen
Thinner outer wall than arteriesThinner layer of muscle and elastic fibres than arteries
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Which is the Artery and Vein???Which is the Artery and Vein???
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Veins also have valves to……keep blood flowing in the right direction
…TOWARDS heart …AWAY
FROM heart
Valves open to allow blood to flow…
Valves close to stop blood flowing…
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Carbon dioxide and other wastes diffuse from the cells to the
blood
Oxygen, nutrients, and hormones diffuse from the blood to the
cells
Capillaries are adapted for ……exchange of materials.
…only one cell thick
…allow plasma to leak in and out
(They are just large enough for a red blood cell to squeeze through)This means that blood in the capillaries moves very…SLOWLY
Gaps between cells in capillary wall…
Wall of capillary is very thin…
The capillaries are very narrow.
Cells in Body Tissues
05/03/2305/03/23 01:2701:27 cottinghamcottingham
The Smallest Blood VesselsThe Smallest Blood Vessels
05/03/2305/03/23 01:2701:27 cottinghamcottingham
ArteriesArteries Vessels that carry Vessels that carry
blood blood AWAYAWAY from the from the heart.heart.
Blood High in Blood High in oxygenoxygen (except (except Pulmonary Artery)Pulmonary Artery)
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
VeinsVeins Vessels that Vessels that
carry blood carry blood TOWARDTOWARD the the heart from body heart from body tissues. One tissues. One direction.direction.
Blood Low in Blood Low in Oxygen (Except Oxygen (Except Pulmonary Vein)Pulmonary Vein)
..
05/03/2305/03/23 01:2701:27 cottinghamcottingham
CapillariesCapillaries Smallest blood Smallest blood
vessels.vessels. 1 layer of 1 layer of
endothelial cells endothelial cells thick. HAVE ONE thick. HAVE ONE WAY VALVES.WAY VALVES.
Red blood cells Red blood cells pass through in pass through in single filesingle file
Gases diffuse in Gases diffuse in lungs.lungs.
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Major Veins and ArteriesMajor Veins and Arteries Inferior and Superior Vena CavaInferior and Superior Vena Cava
– return blood to the right atrium – return blood to the right atrium (BLUE)(BLUE)
Pulmonary ArteryPulmonary Artery – carries blood – carries blood from heart to the lungs (BLUE)from heart to the lungs (BLUE)
Pulmonary Vein Pulmonary Vein – – carries blood carries blood from lungs to the heart (RED)from lungs to the heart (RED)
Aorta –Aorta – carries blood from the carries blood from the heart to all body parts. (RED)heart to all body parts. (RED)
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Pathway of CirculationPathway of Circulation
You must be able to traceYou must be able to traceblood from anywhere in theblood from anywhere in thebody and back to that point.body and back to that point.
Pulmonary CirculationPulmonary Circulation – – involves the LUNGS and ALL involves the LUNGS and ALL parts to the heart except the parts to the heart except the LEFT VENTRICLE and AORTA.LEFT VENTRICLE and AORTA.
Systemic CirculationSystemic Circulation – – begins in the LEFT begins in the LEFT VENTRICLE and ends before VENTRICLE and ends before entering the RIGHT ATRIUM.entering the RIGHT ATRIUM.
Exchange of gases on the Exchange of gases on the cellular level in capillaries.cellular level in capillaries.
Coronary CirculationCoronary Circulation – – supplies blood to the heart.supplies blood to the heart.
Hepatic Portal CirculationHepatic Portal Circulation – – from the digestive system to from the digestive system to the liver. Excess glucose the liver. Excess glucose leaves blood in the liver.leaves blood in the liver.
Renal CirculationRenal Circulation – carries – carries blood to and from the blood to and from the kidney.kidney.
WILLIAM HARVEYWILLIAM HARVEY1578-16571578-1657
READREAD about his discovery of about his discovery of the circulation of blood with the circulation of blood with
the heart acting as the pump.the heart acting as the pump.
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
THE HEARTTHE HEART
05/03/2305/03/23 01:2701:27 cottinghamcottingham
The Heart and Blood Flow in The Heart and Blood Flow in MammalsMammals
General:General: Double-sided pump.Double-sided pump.Blood content:Blood content: Right: low in O2, high in Right: low in O2, high in
CO2CO2 Left: high in O2, low in Left: high in O2, low in
CO2CO2Basic Structure:Basic Structure: Right and Left side Right and Left side
separated by the separated by the SEPTUM.SEPTUM.
AtriumAtrium – upper chambers. – upper chambers. VentriclesVentricles – lower – lower
chambers.chambers. Chambers separated by Chambers separated by
valvesvalves Flow from the heart Flow from the heart
separated by valves.separated by valves.
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
The Mammalian HeartThe Mammalian HeartINNER BODY
Cardiac MuscleCardiac Muscle Myogenic - ABILITY OF
THE HEART TO CONTRACT WITHOUT BEING STIMULATED BY AN “OUTSIDE” NERVE.
Blood supplied by coronary arteries.
Involuntary Striated
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Properties of Cardiac MuscleProperties of Cardiac Muscle Intercalated discs –
separate cardiac muscle cells. Allows for rapid
movement of ions Rapid conduction of
nerve impulse Branched – allow
impulses to move rapidly.
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
The Human HeartThe Human Heart
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Valves and NodesValves and Nodes
05/03/2305/03/23 01:2701:27 cottinghamcottingham
ValvesValvesVALVESVALVES
Atrioventricular – allows Atrioventricular – allows blood to flow between atria blood to flow between atria and ventricleand ventricle
Semilunar – allows blood to Semilunar – allows blood to flow from ventriclesflow from ventriclesCardiac Angiography
05/03/2305/03/23 01:2701:27 cottinghamcottingham
CARDIAC CYCLE – Control of CARDIAC CYCLE – Control of the Heartbeat!!!the Heartbeat!!!
Nodes Nodes Sino Atrial – (SAN) – Sino Atrial – (SAN) –
Wall of right atriumWall of right atrium PacemakerPacemaker Initiates contractions Initiates contractions
Atrioventricular (AVN) – Atrioventricular (AVN) – Wall of lower RA.Wall of lower RA. Receives impulse from SANReceives impulse from SAN
Connecting Fibers – Connecting Fibers – BBundle of Hisundle of His connected to connected to Purkinje Purkinje
TissueTissue pass through septum to base of heart to all pass through septum to base of heart to all
parts of the ventriclesparts of the ventricles
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
• The “pacemaker” sets the tempo The “pacemaker” sets the tempo of the heartbeat.of the heartbeat.
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Cardiac CycleCardiac Cycle
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Cardiac CycleCardiac Cycle1.1. Walls of atria contract (Systole = 0-1)Walls of atria contract (Systole = 0-1)
SAN fires – ventricles about 70% fullSAN fires – ventricles about 70% full Pushes blood from atria to ventriclePushes blood from atria to ventricle AV open; Semilunar closedAV open; Semilunar closed Ventricles fill; volume risesVentricles fill; volume rises
2.2. Walls of ventricles contract(Systole = 1-Walls of ventricles contract(Systole = 1-4.2)4.2)
More powerful; More powerful; Initial rise in blood pressure in ventricles: AV valves close; Initial rise in blood pressure in ventricles: AV valves close; Further rise in BP: SL valves openFurther rise in BP: SL valves open Blood PUMPED into aorta and pulmonary arteryBlood PUMPED into aorta and pulmonary artery Volume decreaseVolume decrease
Events of the Cardiac CycleEvents of the Cardiac Cycle3. 3. Ventricles stop contracting Ventricles stop contracting (diastole = (diastole = 4.2-9)4.2-9)
Pressure fallsPressure falls Semilunar valves close – prevents Semilunar valves close – prevents
backflowbackflow Blood pressure in Vena cava push Blood pressure in Vena cava push
blood into atriablood into atria Ventricular pressure falls below atrial Ventricular pressure falls below atrial
pressure: AV valves openpressure: AV valves open
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
CONTROL OF HEARTRATECONTROL OF HEARTRATE1.1. MyogenicMyogenic
1.1. Pacemaker – region of the heart (wall of Pacemaker – region of the heart (wall of R.A.) responsible for initiating contraction.R.A.) responsible for initiating contraction.
2.2. Nerves from the brainstem carry Nerves from the brainstem carry messages to pacemaker - speed up messages to pacemaker - speed up heartbeatheartbeat
3.3. Adrenaline – carried to heart in blood Adrenaline – carried to heart in blood --- tells pacemaker to speed up --- tells pacemaker to speed up heartbeat.heartbeat.
CardiologyCardiology
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Basic Techniques in Basic Techniques in CardiologyCardiology
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Measuring Heart RateMeasuring Heart Rate Typically uses:Typically uses:
Radial artery in Radial artery in wristwrist
Carotid artery in Carotid artery in neckneck
DO NOT USE DO NOT USE THUMB!THUMB! It has its own pulse.It has its own pulse.
Variables affecting:Variables affecting:
Demand for oxygenDemand for oxygen Demand for glucoseDemand for glucose Removal of CORemoval of CO2 2 ExerciseExercise Body PositionBody Position TemperatureTemperature
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Electrocardiograms (ECG)Electrocardiograms (ECG) P wave – atrial P wave – atrial
systolesystole
QRS – Ventricular QRS – Ventricular SystoleSystole
T – ventricular T – ventricular diastole diastole
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Artificial PacemakersArtificial Pacemakers Inserted to treat Inserted to treat
malfunctioning SAN malfunctioning SAN OROR
A block in the A block in the conduction pathway.conduction pathway.
Can provide a regular Can provide a regular or just when needed or just when needed impusle.impusle.
Regulates heart rate Regulates heart rate and rhythm and rhythm
05/03/2305/03/23 01:2701:27 cottinghamcottingham
PacemakersPacemakers
05/03/2305/03/23 01:2701:27 cottinghamcottingham
DefibrillatorsDefibrillators Treats ventricular
fibrillation
Application of 2 paddles in a diagonal line – with the heart in the middle
Detects fibrillation Electrical shock to
return to normal rhythm
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Stethoscopes and Heart SoundsStethoscopes and Heart Sounds
11stst sound – closing of AV valve (lup) sound – closing of AV valve (lup) 22ndnd sound – closing of SL Valve (dup) sound – closing of SL Valve (dup)
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Measuring Blood PressureMeasuring Blood Pressure Cuff placed around Cuff placed around
upper arm (Brachial upper arm (Brachial Artery)Artery)
Blood is constrictedBlood is constricted Cuff slowly deflatedCuff slowly deflated Stethoscope used for Stethoscope used for
sounds of blood flowsounds of blood flow 11stst sound systolic sound systolic 22ndnd diastolic diastolic
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Blood PressureBlood Pressure
05/03/2305/03/23 01:2701:27 cottinghamcottingham
Hypertension and Hypertension and ThrombosisThrombosis
Causes – not clear Risk factors:
Obesity Lack of exercise Too much salt Too much
alcohol/coffee Smoking Genetic
Consequences: Kidney damage CHD
Causes:Causes: High LDLHigh LDL High SAT/TRANS FATHigh SAT/TRANS FAT Inactivity Inactivity SmokingSmoking HypertensionHypertension EthnicEthnic GeneticGenetic
Consequences:Consequences: Heart AttackHeart Attack StrokeStroke Atherosclerosis Atherosclerosis
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
05/03/2305/03/23 01:2701:27 cottinghamcottingham
ENDEND
05/03/2305/03/23 01:2701:27 cottinghamcottingham