(Circulatory System) ORGAN SYSTEM FOR INTERNAL TRANSPORT
Dec 19, 2014
(Circulatory System)
ORGAN SYSTEM FOR INTERNAL TRANSPORT
Overview: Transport and Exchange Every organism must exchange
materials with its environment Exchanges ultimately occur at the
cellular level In unicellular organisms, these
exchanges occur directly with the environment
For most cells making up multicellular organisms, direct exchange with the environment is not possible
Internal transport and gas exchange are functionally related in most animals
Open and Closed Circulatory Systems
In an open circulatory system, there is no distinction between blood and interstitial fluid, and this general body fluid is more correctly called hemolymph
In a closed circulatory system, blood is confined to vessels and is distinct from the interstitial fluid
Closed systems are more efficient at transporting circulatory fluids to tissues and cells
Heart
Hemolymph in sinusessurrounding organs
Heart
Interstitialfluid
Small branch vesselsIn each organ
Blood
Dorsal vessel(main heart)
Auxiliary hearts Ventral vessels
(b) A closed circulatory system(a) An open circulatory system
Tubular heart
Pores
CIRCULATORY SYSTEMDefiniton
It is a fluid-filled network of tubes (or vessels) through which materials move between the environment and the cells of a multicellular animal.
CIRCULATORY SYSTEMCharacteristic
It connects all parts of an organism in a way that allows individual cells to thrive as well as for organisms to function as a unit.
It is an entirely closed system.
CIRCULATORY SYSTEMFunctionTransport materials needed by cells
OxygenGlucose
Remove waste materials from cellsCarbon dioxideurea
CIRCULATORY SYSTEMMain Component
Pump (heart) Continuously circulates bloodNetwork of tubesArteries- blood away from heartVeins- blood back to the heartBloodFluid that fills the circulatory system
THE HEART
THE HEARTIt is the main organ of
the Circulatory System, which is located between lungs and diaphragm.
It is so powerful that it can pump blood
10, 000 liters of blood daily.
Parts of the Human HeartHeart is actually
made up of two pumps placed side by side:
- onto your right - onto your left
pericardium- protective membrane which surrounds the whole muscular organ
Heart Wall
Three layers of tissueEpicardium: This serous membrane of smooth outer surface of heart
Myocardium: Middle layer composed of cardiac muscle cell and responsibility for heart contracting
Endocardium: Smooth inner surface of heart chambers
Four Chambers of the Heart
1.Right and Left atria (sing.,atrium)- the upper thin walled chamber- collecting chambers of the heart
a. Right atrium(RA)- collects venous unoxygenated blood from your body
b. Left atrium(LA)- receives red oxygenated blood from your lungs
rightatrium
leftatrium
2. Right and Left ventricles - lower thick-walled chambers- the pumping chambers of your heart
a. Right ventricle(RV)- pumps blue venous blood out of your heart and into the lungs for oxygenation
b. Left ventricle(LV)- pumps oxygenated blood out of your heart to all parts of the body
rightventricle
leftventricle
Heart Valves1.Tricuspid
valve- between the right atrium and right ventricle
2. Bicuspid or mitral valve- between the left atrium and left ventricle
3. Pulmonary semilunar valve- between the right ventricle and the pulmonary artery
4. Aortic Semilunar Valve- between the left ventricle and aorta
A muscular wall, or septum, divides your heart into its right and left side.
Superior Vena Cava(SVC)- located at the upper part of your heart and brings blood from your head and arms.
Inferior Vena Cava(IVC)- located at the lower part of your heart and brings blood from the lower parts of your body.
Pulmonary Artery(PA)- carries deoxygenated blood from the right ventricle of your heart to the lungs.
Pulmonary Vein(PV)- brings back oxygenated blood from the lungs to the left atrium of your heart.
Aorta- it is the largest artery in the body. It brings oxygenated blood to all parts of the body.
Blood Flow Through Heart
From lungs
After passing through the capillaries of the lungs, the blood which is now oxygenated returns to the heart in the pulmonary veins.
The left atrium receives blood from the pulmonary vein.
Blood passes through the mitral valve into the left ventricle.
To rest of body
Contraction of the left ventricle pushes blood through the aortic semilunar valve into the aorta. Blood travels to all regions of the body where it feeds cells with oxygen picked up from the lungs and nutrients from the digestive tract.
Deoxygenated blood returns from the rest of the body through the superior and inferior vena cava.
The right atrium receives the deoxygenated blood.
Blood then enters the right ventricle through the tricuspid valve.
To lungs
Contraction of the right ventricle pushes blood through the pulmonary semilunar valve into the pulmonary arteries in which it travels to the lungs.
Then cycle repeats again....
BLOOD VESSELS
BLOOD VESSELSAre hollow tubes that carry blood
through in a never ending stream.Responsible in carrying blood
between the heart, different tissues and organs of the body
Have the ability to expand to allow more blood to flow
Can also contract to help control blood flow
BLOOD VESSELS
Three types:ArteriesCapillariesVeins
BLOOD VESSELSArteries
Elastic, muscular tubes that carry the blood away from left ventricle to the capillaries
Have thicker walls3 layers thick:
Tunica intimaTunica mediaTunica externa
Arteries that connect to the capillaries are called arterioles
DID YOU KNOW THAT...•All arteries carries oxygenated blood except pulmonary arteries
BLOOD VESSELSCapillaries
Smallest working unit in the blood vessel that connects arterioles and venules
Walls are only one cell thick to facilitate exchange of nutrients and oxygen
Forms a network called capillary bedHave sphincters that regulates the flow of blood.
Fig. 42-15
Precapillary sphinctersThoroughfarechannel
Arteriole
Capillaries
Venule
(a) Sphincters relaxed
(b) Sphincters contracted
Arteriole Venule
Capillary Exchange
35
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venulearteriole
water
oxygenglucose
salt
water
wastes
osmotic pressureblood pressure
to heartfrom heart
Arterial endBlood pressure is higherthan osmotic pressure.Net pressure out. amino
acidscarbondioxide
Venous endOsmotic pressure is higherthan blood pressure.Net pressure in.
plasmaprotein
smoothmuscle fiber
Tissue fluid
BLOOD VESSELSVeins
Carry blood from capillaries to heart
Veins that connects to capillaries are called venules
Are not thick as arteriesHave also three wallsContains valve unlike arteries
Fig. 42-10Artery Vein
SEM100 µm
Endothelium
Artery
SmoothmuscleConnectivetissue Capillary
Basal lamina
Endothelium
Smoothmuscle
Connectivetissue
Valve
Vein
Arteriole Venule
Red blood cell
Capillary
15 µ
mLM
Circulation
CIRCULATIONPulmonary circulation
Carries the blood to and from the lungs
Right heart
Oxygen-depleted blood from the body leaves the systemic circulation when it enters the right heart, more specifically the right atrium through the superior (upper) vena cava and inferior (lower) vena cava. The blood is then pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle. Blood is then pumped through the semilunar valve and into the pulmonary artery.
ArteriesFrom the right ventricle, blood is pumped
through the pulmonary semilunar valve into the left and right pulmonary arteries (one for each lung) and travels through the lungs.
LungsThe pulmonary arteries carry deoxygenated
blood to the lungs, where it releases carbon dioxide and picks up oxygen during respiration. Arteries are further divided in to very fine branches called the capillaries.
VeinsThe oxygenated blood then leaves the lungs
through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. This blood then enters the left atrium, which pumps it through the bicuspid valve, also called the mitral or left atrioventricular valve, into the left ventricle.
Left heartThe blood is then distributed to the
body through the systemic circulation before returning again to the pulmonary circulation.
CIRCULATIONSystemic Circulation
refers to the part of the circulatory system in which the blood leaves the heart, services the body's cells, and then re-enters the heart
ArteriesOxygenated blood enters
the systemic circulation when leaving the left ventricle, through the aortic semilunar valve. The first part of the systemic circulation is the aorta, a massive and thick-walled artery. The aorta arches and branches into major arteries to the upper body before passing through the diaphragm, where it branches further into arteries which supply the lower parts of the body.
CapillariesArteries branch into
small passages called capillaries. The capillaries merge to bring blood into the veinous system.
VeinsAfter their passage
through body tissues, capillaries merge once again into venules, which continue to merge into veins. The venous system finally coalesces into two major veins: the superior vena cava (roughly speaking draining the areas above the heart) and theinferior vena cava (roughly speaking from areas below the heart). These two great vessels empty into the right atrium of the heart.
ArteriesOxygenated blood enters
the systemic circulation when leaving the left ventricle, through the aortic semilunar valve. The first part of the systemic circulation is the aorta, a massive and thick-walled artery. The aorta arches and branches into major arteries to the upper body before passing through the diaphragm, where it branches further into arteries which supply the lower parts of the body.
CIRCULATIONOther types of circulation:Coronary Circulation
Blood circulation in the heartRenal Circulation
involves the blood flow through the kidneys
Portal circulationRefers to the blood flow involving the liver
BLOOD
Blood Composition and Function
In invertebrates with open circulation, blood (hemolymph) is not different from interstitial fluid
Blood in the circulatory systems of vertebrates is a specialized connective tissue
Blood consists of several kinds of cells suspended in a liquid matrix called plasma
The cellular elements occupy about 45% of the volume of blood
Blood: Homeostasis Functions
Transports substances to and from capillaries for exchange with tissue fluid
Guards against pathogen invasionRegulates body temperatureBuffers body pHMaintain osmotic pressureClots prevent blood/fluid loss
Plasma
Blood plasma is about 90% waterAmong its solutes are inorganic salts in
the form of dissolved ions, sometimes called electrolytes
Another important class of solutes is the plasma proteins, which influence blood pH, osmotic pressure, and viscosity
Various plasma proteins function in lipid transport, immunity, and blood clotting
Cellular Elements
Suspended in blood plasma are two types of cells:Red blood cells (erythrocytes) transport oxygenWhite blood cells (leukocytes) function in defense
Platelets, a third cellular element, are fragments of cells that are involved in clotting
Composition of Blood
56
Blood
Plasma 46-63% Formed Elements 37-54%
Plasma Protein 7% Water 92% Other Solutes 1% Platelets RBC 99.9% WBC
Albumin
Fibrinogen
Globulin
Regulatory Proteins
Eg. Electrolytes
Monocytes
Basophils
Eosinophils
Neatrophils
Lymphocytes
Fig. 42-17
Plasma 55%
Constituent Major functions
Water Solvent forcarrying othersubstances
Ions (blood electrolytes)
Osmotic balance,pH buffering, andregulation ofmembranepermeability
SodiumPotassiumCalciumMagnesiumChlorideBicarbonate
Osmotic balancepH buffering
Clotting
Defense
Plasma proteins
Albumin
Fibrinogen
Immunoglobulins(antibodies)
Substances transported by blood
Nutrients (such as glucose, fatty acids, vitamins)Waste products of metabolismRespiratory gases (O2 and CO2)Hormones
Separatedbloodelements
Cellular elements 45%
Cell type FunctionsNumberper µL (mm3) of blood
Erythrocytes(red blood cells)
5–6 million Transport oxygenand help transportcarbon dioxide
Leukocytes(white blood cells)
5,000–10,000 Defense andimmunity
Basophil
Neutrophil
Eosinophil
Lymphocyte
Monocyte
Platelets Blood clotting250,000–400,000
RED BLOOD CELLS
Red blood cells, or erythrocytes, are by far the most numerous blood cells
They transport oxygen throughout the body
They contain hemoglobin, the iron-containing protein that transports oxygen
Erythrocytes
WHITE BLOOD CELLS
There are five major types of white blood cells, or leukocytes: monocytes, neutrophils, basophils, eosinophils, and lymphocytes
They function in defense by phagocytizing bacteria and debris or by producing antibodies
They are found both in and outside of the circulatory system
PLATELETS
When the endothelium of a blood vessel is damaged, the clotting mechanism begins
A cascade of complex reactions converts fibrinogen to fibrin, forming a clot
A blood clot formed within a blood vessel is called a thrombus and can block blood flow
• Platelets are fragments of cells and function in blood clotting
Collagen fibersPlateletplug
Platelet releases chemicalsthat make nearby platelets sticky
Clotting factors from:PlateletsDamaged cellsPlasma (factors include calcium, vitamin K)
Prothrombin Thrombin
Fibrinogen Fibrin5 µm
Fibrin clot
Red blood cell
Fig. 42-18-4
Stem Cells and the Replacement of Cellular Elements
The cellular elements of blood wear out and are replaced constantly throughout a person’s life
Erythrocytes, leukocytes, and platelets all develop from a common source of stem cells in the red marrow of bones
The hormone erythropoietin (EPO) stimulates erythrocyte production when oxygen delivery is low
Fig. 42-19
Stem cells(in bone marrow)
Myeloidstem cells
Lymphoidstem cells
LymphocytesB cells T cells
Erythrocytes
Platelets
Neutrophils
BasophilsEosinophils
Monocytes
DISORDERS AND DISEASES OF THE
HUMAN CIRCULATORY
SYSTEM
ATHEROSCELEROSIS
ATHEROSCELEROSIS What is atherosclerosis?
Hardening and narrowing of the arteries due to growing plaques
These plaques can behave in three different ways:•They can stay wihin the artery wall•They can grow in a slow manner eventually causing significant blokage•They can rupture, allowing blood to clot.
ATHEROSCELEROSIS What are its
causes? Smoking High cholesterol High blood pressure
Diabetes Abdominal obesity
Stress
Not eating fruits and
Vegetables
Excess alcohol intake
Not exercising regularly
ATHEROSCELEROSIS What are the treatments for
atherosclerosis? Lifestyle changes Medication Bypass surgery
ATHEROSCELEROSIS How can we prevent
atherosclerosis? Avoid Smoking Avoid stress and depression Eat fruits and Vegetables Exercise regularly
HEART FAILURE
HEART FAILURE What is heart failure?
Condition wherein the heart is unable to to provide sufficient pump action to maintain blood flow required by the body
HEART FAILURE What are its symptoms?
Heart failure on the left side of the body Breathlessness Frothy spit with cough
Heart failure n the left side of the body Swollen ankles Swollen legs Enlarged liver Enlarged stomach
HEART FAILURE What are its symptoms?
Heart failure on both sides of the body Dizziness and/or confusion Nausea Constipation Loss of appetite
HEART FAILURE What are its
causes? Diabetes Obesity Smoking Hypertension Heart attack Depression among heart disease patients
Inherited heart disease
Congenital heart defects
Anemia Faulty heart valves
Heart arrhythmias
HEART FAILURE What are the treatment for heart
failure? Medications
ACE inhibitors Diuretics Digoxin
Surgery Pacemaker that uses heartbeat Surgery that reshapes scarred left ventricle
Exercise training
HEART FAILURE How can we prevent heart failure?
Give up smoking Eat sensibly Exercise regularly Consume alcohol within recommended level
Get at least 7 hours of sleep Avoid mental stress
SEPSIS
SEPSISWhat is sepsis?
Condition when the body is fighting a severe infection
SEPSISWhat are its symptoms?
Chills and severe shakingVery fast heartbeatLow blood pressureDizziness and decresaed urination
Skin rashesFeverMay develop pain in the joints of the wrists, elbows, back, hips, knees and ankles
SEPSISWhat are the causes of sepsis?
BacteriaViruses and fungiPneumoniaUrinary tract infectionAppendicitisInfection that develop after surgery
SEPSISWhat are the treatment for this?
Medications given intravenouslyIV salt solutionIf result show an infection in the abdomen, either drainage of the infection by the placement of tubes or surgery may be necessary
SEPSIS How can we prevent sepsis?
Following recommended immunization schedules may reduce risk in children
Hospital-related infections leading to sepsis may be decreased by strictly following hand washing and hygiene protocol.
ANEMIA
ANEMIAWhat is anemia?
Condition wherein the blood does not carry sufficient amount of oxygen due to iron defficiency
ANEMIAWhat are the causes of anemia?
Blood lossDecreased or faulty red blood cell production
Destruction of red blood cells
ANEMIAWhat are its symptoms?
Easy fatigue and loss of energyRapid heartbeatDizzinessLeg crampsInsomnia
ANEMIAWhat are the treatments for
anemia?Creating a check-up schedule with doctor
Follow doctor’s medicationSupplement your oxygenSchedule blood transfusion at the advice of your doctor
ANEMIAHow can we prevent anemia?
Check if your at riskEat a diet rich in iron and vitamin C
Take iron supplement to make sure your getting enough
Avoid excessive dieting and over-exercising
Avoid donating blood
STROKE
STROKEWhat is a stroke?
happens when blood flow to a part of the brain stops. A stroke is sometimes called a "brain attack."
If blood flow is stopped for longer than a few seconds, the brain cannot get blood and oxygen. Brain cells can die, causing permanent damage.
STROKEWhat are the causes of stroke?
Blood supply to brain is interrupted or reduced
A blocked artery (ischemic stroke) or a leaking or burst blood vessel (hemorrhagic stroke)
STROKEWhat are the treatment for stroke?
Medical treatmentAspirinStroke recovery and rehabilitation
STROKEHow can we prevent stroke?
Healthy dietAntiplatelet therapyControl of sugarAvoid smokingManagement of high blood pressure
STROKEWhat are its symptoms?
Sudden numbness of the face, arm or leg, especially on one side of the body
Sudden trouble seeing in one or both eyes
Sudden trouble walking, dizziness, or loss of balance and coordination
Sudden severe headache with no known cause
Sudden confusion or trouble in speaking and understanding