Circulatory SystemCirculatory System

Circulatory SystemCirculatory System

ComponentsComponents

I. HeartI. HeartII. Blood VesselsII. Blood Vessels

Veins, Capillaries, and Veins, Capillaries, and ArteriesArteries

III.III. Components of Components of Blood Blood

IV.IV. Lymphatic SystemLymphatic SystemV.V. Blood TypeBlood TypeVI.VI. Circulatory Circulatory

ProblemsProblems

(**Closed System**)(**Closed System**)

A. CirculationA. Circulation

• Muscle contractions Muscle contractions cause blood to pumpcause blood to pump

• Pulmonary Pulmonary CirculationCirculation -Blood -Blood pumped from right side pumped from right side of heart to lungsof heart to lungs

• Systemic Circulation - Systemic Circulation - Blood pumped to the Blood pumped to the rest of the bodyrest of the body

Capillaries of head and arms

Capillaries of abdominal organs and legs

Inferior vena cava

Pulmonary veinCapillaries

of right lung

Superior vena cava

Aorta Pulmonary artery

Capillaries of left lung

I. Heart

The HeartThe HeartI.I. HeartHeart

B. StructureB. Structure• Composed mainly of muscleComposed mainly of muscle• PericardiumPericardium - Protective - Protective

layer surrounding the heartlayer surrounding the heart• MyocardiumMyocardium – muscle found – muscle found

in the heart walls, responsible in the heart walls, responsible for pumping bloodfor pumping blood

• Septum – Septum – Divides heart into Divides heart into 2 halves, 2 halves,

• Restricts mixing of bloodRestricts mixing of blood• Each side has two chambersEach side has two chambers

• AtriumAtrium (Upper Chamber) (Upper Chamber) – Receives blood– Receives blood

• VentricleVentricle (Lower (Lower Chamber) – pumps blood Chamber) – pumps blood out of the heartout of the heart

• Contains Valves that keep Contains Valves that keep blood flowing in one directionblood flowing in one direction

Pumps enough blood to fill an Olympic-sized Pumps enough blood to fill an Olympic-sized swimming pool a yearswimming pool a year

Click To Enlarge

Superior Vena CavaLarge vein that brings oxygen-poor blood from the upper part of the body to the right atrium

AortaBrings oxygen-rich blood from the left ventricle to the rest of the body

Pulmonary ArteriesBring oxygen-poor blood to the lungs

Pulmonary VeinsBring oxygen-rich blood from each of the lungs to the left atrium

Pulmonary ValvePrevents blood from flowing back into the right ventricle after it has entered the pulmonary artery

Right Atrium

Tricuspid ValvePrevents blood from flowing back into the right atrium after it has entered the right ventricle

Inferior Vena CavaVein that brings oxygen-poor blood from the lower part of the body to the right atrium

Right Ventricle

Septum

Left Ventricle

Mitral ValvePrevents blood from flowing back into the left atrium after it has entered the left ventricle

Aortic ValvePrevents blood from flowing back into the left ventricle after it has entered the aorta

Left Atrium

Question: What is the advantage of a 4-chambered heart?

I. Heart

Coronary Artery:Coronary Artery:Supplies the heart muscle itself with Supplies the heart muscle itself with

bloodblood

C. HeartbeatC. Heartbeat Sinoatrial Node (Pacemaker)Sinoatrial Node (Pacemaker)

• Located in the right atriumLocated in the right atrium• Cardiac muscles contract in waves causing blood to leave the atria into Cardiac muscles contract in waves causing blood to leave the atria into

ventricleventricle• Stimulated by nerve impulse from the medullaStimulated by nerve impulse from the medulla

Atrioventricular NodeAtrioventricular Node• Location – base of right atrium & beginning of right ventricleLocation – base of right atrium & beginning of right ventricle• Transfers impulse from atria muscles and transfers them to ventricle musclesTransfers impulse from atria muscles and transfers them to ventricle muscles• Ventricles contract causing blood to leave heartVentricles contract causing blood to leave heart

I. Heart C. HeartbeatC. Heartbeat Each heartbeat is Each heartbeat is

called a cardiac called a cardiac cycle: two atria cycle: two atria contract then two contract then two ventricles contract ventricles contract (systole), and the (systole), and the entire heart relaxes entire heart relaxes (diastole)(diastole)

A normal heart beats A normal heart beats 70 times per minute.70 times per minute.• Makes a “lub-dub”

sound as the valves of the heart are opening and closing.

I. Heart1. Electrocardiogram1. Electrocardiogram (ECG or(ECG or EKG)EKG) A test that records the A test that records the

electrical activity of the electrical activity of the heart.heart.

The The P waveP wave represents represents contraction (systole) of contraction (systole) of the atria.the atria.

The The QRS waveQRS wave contraction of the contraction of the ventricleventricle

The T wave The T wave The relaxation of the The relaxation of the muscle (diastole)muscle (diastole)

Question: What are some problems associated with the Sinoatrial Node? How can it be fixed?

I. Heart

2. Pacemaker2. Pacemaker Abnormal Abnormal

heartbeats can be heartbeats can be controlled by an controlled by an artificial artificial pacemaker that is pacemaker that is run on batteriesrun on batteries

II. Blood VesselsII. Blood Vessels

II. Blood Vessels C. ArteriesArteries

4. Blood Pressure4. Blood Pressure Definition: Force that is exerted by the blood upon the Definition: Force that is exerted by the blood upon the

walls of the blood vessels.walls of the blood vessels. a. Regulated in 2 ways:a. Regulated in 2 ways:

• Sensory –neurons attached to blood vessels detect blood Sensory –neurons attached to blood vessels detect blood pressurepressure

If too low – neurons (nerve cells) stimulate nervous system If too low – neurons (nerve cells) stimulate nervous system to increase heart rateto increase heart rate

If too high – stimulate nervous system to decrease (slow If too high – stimulate nervous system to decrease (slow down) heart ratedown) heart rate

• KidneysKidneys When blood pressure is high – kidneys remove water from When blood pressure is high – kidneys remove water from

the bloodthe blood When blood pressure is low – kidneys keep water volume When blood pressure is low – kidneys keep water volume

high in bloodhigh in blood

III. Components of BloodIII. Components of Blood

Blood is composed Blood is composed of:of:

• 55% plasma55% plasma

• 45% blood cells45% blood cells red blood cellsred blood cells white blood cellswhite blood cells plateletsplatelets

III. Components of BloodIII. Components of Blood

A. PlasmaA. Plasma Composes 55% of blood volume Composes 55% of blood volume Centrifuged BloodCentrifuged Blood 90% water and 10% dissolved gasses, wastes, 90% water and 10% dissolved gasses, wastes,

nutrients, salts and proteins (Plasma Proteins)nutrients, salts and proteins (Plasma Proteins)• Albumins, Globulins and FibrinogenAlbumins, Globulins and Fibrinogen

Whole Blood Sample

Sample Placed in Centrifuge

Blood Sample that has been Centrifuges

Plasma

Platelets

White Blood Cells

Red Blood Cells

III. III. Components of BloodComponents of Blood

B. Red Blood Cells B. Red Blood Cells (Erythrocytes)(Erythrocytes)• Transport oxygen Transport oxygen

and carbon dioxideand carbon dioxide• Uses Uses

Hemoglobin – Hemoglobin – iron containing iron containing protein that protein that binds to oxygenbinds to oxygen

• Disc shaped to Disc shaped to increase surface increase surface areaarea

• One milliliter One milliliter contains 5 millioncontains 5 million

III. III. Components of BloodComponents of Blood

C. White Blood Cells C. White Blood Cells (Leukocytes)(Leukocytes)• Fight infection Fight infection • 5 Types5 Types: :

neutrophils, neutrophils, eosinophils, eosinophils, basophils, basophils, lymphocytes and lymphocytes and monocytes (located monocytes (located in lymph vessels)in lymph vessels)

• Located in Located in Circulatory and Circulatory and Lymphatic SystemsLymphatic Systems

Cell Type

Neutrophils

Eosinophils

Basophils

Monocytes

Lymphocytes

Function

Engulf and destroy small bacteria and foreign substancesAttack parasites; limit inflammation associated with allergic reactions

Release histamines that cause inflammation; release anticoagulants, which prevent blood clotsGive rise to leukocytes that engulf and destroy large bacteria and substancesSome destroy foreign cells by causing their membranes to rupture; some develop into cells that produce antibodies, which target specific foreign substances

White Blood Cells

III. Components of Blood

D. Platelets (Thrombocytes)

• More numerous than WBC’s: 250,000 platelets in a small drop of blood

• Much smaller than RBC’s• Are fragments of cells• Made in the bone marrow• Live ~ 5 days• Aid in forming blood clots• Adhere to site of injury and

release chemicals to help blood clot

IV. Lymphatic SystemIV. Lymphatic SystemA. Network of nodes, vessels A. Network of nodes, vessels

and organsand organs

B. Primary function = return B. Primary function = return fluid lost by the blood to the fluid lost by the blood to the Circulatory SystemCirculatory System

C. Contains fluid called LymphC. Contains fluid called Lymph

D. Restricts backward flow by D. Restricts backward flow by the use of valvesthe use of valves

E. Nodes are used to trap E. Nodes are used to trap bacteria bacteria

F. OrgansF. Organs• SpleenSpleen

• Harbors Phagocytes & Harbors Phagocytes & removes damaged blood removes damaged blood cellscells

• Thymus Thymus • Location of matured T CellsLocation of matured T Cells

Superior vena cava

Lymph nodes

Thymus

Heart

Thoracic duct

Spleen

Lymph vessels

Blood Type

Antigens on RBC’s

Antibodies in Plasma

Can Receive Blood From…

Can Donate To…

A A Anti-B O and A A and AB

B B Anti-A O and B B and AB

AB AB None A, B, AB and O

AB

O O Anti-A &Anti-B

O A, B, AB, and O

V. Blood Types

*AB = universal recipient (can receive all blood types)

* O = universal donor (can donate to all blood types)

Blood Type of Donor

A

B

AB

O

Blood Type of Recipient

A B AB O

Unsuccessful transfusion Successful transfusion

VI. Circulatory ProblemsVI. Circulatory Problems

AtherosclerosisAtherosclerosis – – Condition in which lipids collect under the Condition in which lipids collect under the inner lining of damaged artery walls, eventually narrowing inner lining of damaged artery walls, eventually narrowing or blocking the artery and obstructing blood flow.or blocking the artery and obstructing blood flow.

Heart MurmurHeart Murmur – – Whooshing sound Whooshing sound caused by the back flow of blood from the caused by the back flow of blood from the left ventricle across the mitral valve back into left ventricle across the mitral valve back into the left atriumthe left atrium

AnemiaAnemia – – A decrease in number of A decrease in number of

healthy red blood cellshealthy red blood cells

Coronary ThrombosisCoronary Thrombosis – – (Heart Attack) Blockage of coronary (Heart Attack) Blockage of coronary arteries preventing oxygen to reach a particular area of the heart arteries preventing oxygen to reach a particular area of the heart musclemuscle

Atherosclerosis

VI. Problems Cont.VI. Problems Cont.

StrokeStroke – – Occurs when blood vessels leading to or in the brain Occurs when blood vessels leading to or in the brain clot or burst causing that area of the brain to die due to clot or burst causing that area of the brain to die due to lack of oxygenlack of oxygen

Sickle Cell

Rheumatic FeverRheumatic Fever – – A serious inflammatory A serious inflammatory condition which follows Streptococcal pharyngitiscondition which follows Streptococcal pharyngitis (strep throat). Can damage valves in the heart.strep throat). Can damage valves in the heart.

LeukemiaLeukemia – – cancer that originates in the blood – causes cancer that originates in the blood – causes overproduction of leukocytesoverproduction of leukocytes

Sickle Cell AnemiaSickle Cell Anemia – – Genetic disorder, resulting Genetic disorder, resulting in misshaped red blood cellsin misshaped red blood cells

How is Blood Pressure How is Blood Pressure Measured?Measured?

b. Sphygmonometerb. Sphygmonometer Normal Blood Pressure: Normal Blood Pressure:

120/80120/80 120 – ventricles contract 120 – ventricles contract

(systolic)(systolic) 80 - ventricles relax 80 - ventricles relax

(diastolic)(diastolic) c. Hypertension – c. Hypertension –

excessively high blood excessively high blood pressure, medical pressure, medical consequences (140/90 or consequences (140/90 or higher), can be caused higher), can be caused by alcohol, smoking, diet by alcohol, smoking, diet and distressand distress

•Hypertension Video