Fisiologi Peredaran Darah · 2010. 5. 26. · Fisiologi Peredaran Darah Tahun ajaran 2009-20010....
Transcript of Fisiologi Peredaran Darah · 2010. 5. 26. · Fisiologi Peredaran Darah Tahun ajaran 2009-20010....
Fisiologi Peredaran Darah
Tahun ajaran 2009-20010
Komponen Sistem Peredaran darah
1. Jantung2. Pembuluh Darah
3 Sel sel Darah3. Sel-sel Darah
The circulatory system keeps blood y y ppumping despite gravity’s pull
– Muscle contractions help bl d t l hill i thblood travel uphill in the veins of a giraffe’s long legslegs
– The wriggling of the corn snake squeezes its veinssnake squeezes its veins and increases circulation
Fungsi SPD
– It transports O2 and nutrients to cells – It takes away CO2 and other wastes
Kapiler merupakan bagian SPD yang berhubungan langsung p p g y g g g gdengan jaringan tubuh
Capillary
Redbloodcell
Keluar masuk substansi dari/ke jaringan yang jauh kapiler dibantu oleh cairan interstisial cairan interstisial
Capillary
INTERSTITIALFLUID
Diffusion ofmolecules
Tissuecell
Sistem Peredaran DarahSistem Peredaran DarahSistem Terbuka Pores
Tubular heart
Sistem tertutup ArterioleCapillary beds
Artery(O2-rich blood)
Venule
Vein
AtriumAtrium
VentricleHeartArtery
(O2-poor blood)Gillcapillaries
FISHES AMPHIBIANS REPTILES (EXCEPT BIRDS) MAMMALS AND BIRDS( )
Lung capillaries Lung capillariesLung and skin capillariesGill capillaries
P l t P lA t RightPulmocutaneouscircuit
Pulmonarycircuit
Pulmonarycircuit
Atrium (A)
Heart:ventricle (V)
Artery Gillcirculation
AV VV VV
A A A AALeft Systemicaorta
Right systemicaorta
Right Left Right Left Right Left Systemic
circuitSystemic
circuitSystemic
circulationVein
V VV
Systemic capillaries Systemic capillaries Systemic capillaries Systemic capillariesFigure 42.4
7Capillaries ofH d d
Superiorvena cava
Capillaries Capillaries
Head and armsvena cava
Pulmonaryartery
Pulmonaryartery
Capillariesof right lung
Capillariesof left lung
6
Aorta9
23 3
411
Pulmonaryvein
Pulmonaryi
RIGHT VENTRICLE
1 LEFT ATRIUM5
LEFT VENTRICLE10
RIGHT ATRIUM
veinvein
Capillaries of
Inferiorvena cava
Aorta
8
Capillaries ofabdominal organsand legsSPD Manusia
Struktur Jantung
Pulmonaryartery
Superior
Aorta
PulmonarySuperiorvena cava
RIGHTATRIUM
yartery
LEFTATRIUM
Pulmonaryveins Pulmonary
veins
Semilunarvalve
Atrioventricular
Semilunarvalve
Atrioventricularvalve
Inferiorvena cava
Atrioventricularvalve
vena cava
RIGHTVENTRICLE
LEFTVENTRICLE
The cardiac cycle
Semilunarvalvesclosed
Atrial systole; ventricular diastole
2
Semilunarvalvesopen
0.1 sec
0.3 sec
AV valvesopen
open0.4 sec
AV valvesclosedAtrial and
ventricular1
ventricular diastole Ventricular systole;
atrial diastole3
The control of heart rhythm
2 Signals are delayedat AV node.
1 Pacemaker generates wave of signals
3 Signals passto heart apex.
4 Signals spreadThroughout
to contract. ventricles.
SA node AV node Bundlebranches
(pacemaker)Heartapex
Purkinjefibers
Figure 42.8ECG
Ritmisitas Kontraksi-Relaksasi Jantung
DiastoleBlood flows from the veins into the heart chambers
Heart isrelaxed.AV valves
1 2 Atriacontract.
the heart chambers AV valvesare open.
SYSTOLE0.1 sec
• Systole– The atria briefly
3 Ventriclescontract.Semilunarvalvesare open.
0.4 sec0.3 sec
ycontract and fill the ventricles with bloodTh th t i l
p
DIASTOLE– Then the ventricles
contract and propel blood out
• Heart valves prevent backflowHeart valves prevent backflow
C di t t• Cardiac output – The amount of blood pumped into the aorta by
th l ft t i l i tthe left ventricle per minute
Blood pressure depends on •cardiac outputcardiac output
•resistance of vessels
The pacemaker sets the tempo of the heartbeat
The SA node (pacemaker) generates electrical signals that trigger the contraction of the atria
The AV node then relays these signals to the ventricles
Pacemaker AV nodeSpecialized
l fibPacemaker(SA node)
Rightatrium
AV node muscle fibers
1 2 3 4
Rightventricle
ECG
Blood pressure
Blood pressurereading: 120/70
A typical blood pressure reading for a 20-year-oldis 120/70. The units for these numbers are mm of mercury (Hg); a blood pressure of 120 is a force that can support a column of mercury 120 mm high.
1 The cuff is loosened further until the blood flows freelythrough the artery and the sounds below the cuff
disappear. The pressure at this point is the diastolic pressure remaining in the artery when the heart is relaxed.
4
Rubber cuffinflatedwith air
120 120
Pressurein cuff above 120
Pressurein cuff below 120
Pressurein cuff below 70
70
Artery
Sounds audible instethoscope
Sounds stop
ArteryArteryclosed
A sphygmomanometer, an inflatable cuff attached to apressure gauge, measures blood pressure in an artery.The cuff is wrapped around the upper arm and inflated until the pressure closes the artery, so that no blood
2 A stethoscope is used to listen for sounds of blood flow below the cuff. If the artery is closed, there is no pulse below the cuff. The cuff is gradually deflated until blood begins to flow into the forearm, and sounds from blood
3
Figure 42.12
flows past the cuff. When this occurs, the pressure exerted by the cuff exceeds the pressure in the artery.
pulsing into the artery below the cuff can be heard with the stethoscope. This occurs when the blood pressure is greater than the pressure exerted by the cuff. The pressure at this point is the systolic pressure.
Measuring blood pressure can reveal cardiovascular problemsp
Blood pressure is measured as systolic and diastolic pressures
Blood pressure120 systolic80 diastolic80 diastolic(to be measured)
Rubber cuff
Pressurein cuffbelow120
Pressurein cuffbelow 80
Pressurein cuffabove120
inflated with air
S d
Artery
Soundsaudible instethoscope
Soundsstop
Arteryclosed
1 2 3 4
Epithelium
Epithelium Basementmembrane
Valve
Smoothmuscle
ConnectiveCAPILLARY
Epithelium
Smoothmuscle
Connectivetissue
ARTERY
Connectivetissue
VEIN
ARTERIOLEVENULE
Pressure is highest in Systolicgthe arteries
Diastolicpressure
ypressure
– It drops to zero by the
Relative sizes andnumbersof blood zero by the
time the blood
vessels
blood reaches the veins
Three factors keep blood moving back to the heart
– muscle contractions– breathing– one-way valvesy
Direction ofblood flowin vein
Valve (closed)Skeletal muscle
Valve (open)
Hypertension is persistent systolic pressure higher than 140 mm Hg and/or diastolic pressure higher than 90 mm Hg
– It is a serious cardiovascular problem
e.g Heart Attack
What is a heart attack ?
A heart attack is damage that occurs when a coronary feeding the heart is blocked
Aorta
Rightcoronaryartery
Aorta
L ftartery Leftcoronaryartery
Blockage
Dead muscle tissue
Blood vessel blockage is usually due to blood clots
(see case of heart disease)
Connectivetissue
Smoothmuscle Epithelium Plaque
Smooth muscle controls the distribution of blood
Muscular constriction of arterioles and precapillary sphincters controls the flow through capillariesg p
Precapillary sphincters Thoroughfarechannel
Thoroughfarechannel
CapillariesArteriole Venule Arteriole Venule
1 Sphincters relaxed 2 Sphincters contracted
The transfer of materials between the blood and interstitial fluid can occur byoccur by
– leakage through clefts in the capillary wallsg g p y– diffusion through the wall– blood pressureblood pressure– osmotic pressure
Tissue cells
Arterialend of
ill
Tissue cells
Osmoticpressure
Osmoticpressure Venous
end ofillcapillary
Bloodpressure
Bloodpressure
capillary
INTERSTITIALFLUID NET PRESSURE
OUTNET PRESSURE
IN
Withdrawblood
Place in tubePLASMA 55%
CONSTITUENT MAJOR FUNCTIONS
Centrifuge
CELLULAR ELEMENTS 45%
WaterSolvent forcarrying othersubstances
Salts
CELL TYPE NUMBER(per mm3 of blood)
FUNCTIONS
Erythrocytes(red blood cells) 5–6 million Transport of
oxygenOsmotic balance,pH buffering, andregulation ofmembranepermeability
SodiumPotassiumCalciumMagnesiumChlorideBicarbonate
oxygen (and carbon dioxide)
Leukocytes(white blood cells) 5,000–10,000
Defense andimmunity
Plasma proteinsOsmotic balance,pH bufferingClottingImmunity
Albumin
FibrinogenImmunoglobins(antibodies)
, , immunity
BasophilEosinophil
Lymphocyte
( )
Substances transported by bloodNutrients (e.g., glucose, fatty acids, vitamins)Waste products of metabolismRespiratory gases (O2 and CO2)Hormones
Eosinophil
NeutrophilMonocyte
Platelets 250,000–400 000 Blood clotting400,000
• Red blood cells contain hemoglobin
White blood cells function both inside and outside the circulatory system
g– Hemoglobin enables the
transport of O2yThey fight infections and cancer
Basophil Eosinophil
Monocyte
Neutrophil Lymphocyte
When a blood vessel is damaged platelets responddamaged, platelets respond
They help trigger the formation of an insoluble fibrin clot that plugs the leak
Injury to lining of bloodvessel exposes connectivetissue; platelets adhere
1 2 3Platelet plug forms Fibrin clot trapsblood cells
Connectivetissue
Platelet releases chemicalsthat make nearby platelets sticky
Plateletplug
Clotting factors from:g
Platelets
Damaged cells
Calcium andother factorsin blood plasma
Prothrombin Thrombin
Fibrinogen FibrinFibrinogen Fibrin
All blood cells develop from stem cells in bone marrowcells in bone marrow
Such cells may prove valuable for treating certain blood disorders
Peran Darah sebagai Immun system