Chapter 13Chapter 13

Heart and CirculationHeart and Circulation

General features of the circulatory system   The main propulsive organ is the

______

  An_______ system distributes blood and is a pressure reservoir  

Capillaries have low ________ and transfer material between blood and tissues  

A venous system ________ blood under _________ pressure and returns the blood to the heart

Functions of the Circulatory Functions of the Circulatory SystemSystem

►Transportation:Transportation: Respiratory:Respiratory:

►Transport 0Transport 022 and C0 and C02.2.

Nutritive:Nutritive:►Carry absorbed __________ products to liver Carry absorbed __________ products to liver

and to tissues.and to tissues. Excretory:Excretory:

►Carry metabolic wastes to _________ to be Carry metabolic wastes to _________ to be excreted.excreted.

Functions of the Circulatory Functions of the Circulatory System System (continued)(continued)

►Regulation:Regulation: Hormonal: Hormonal:

►Carry hormones to target tissues to produce their Carry hormones to target tissues to produce their effects.effects.

Temperature: Temperature: ►Divert blood to cool or warm the body.Divert blood to cool or warm the body.

Protection:Protection:►Blood clotting. Blood clotting.

Immune: Immune: ►Leukocytes, cytokines and complement act against Leukocytes, cytokines and complement act against

pathogens.pathogens.

Components of Circulatory Components of Circulatory SystemSystem

► Cardiovascular System (CV):Cardiovascular System (CV): Heart: Heart:

► Pumping action creates _________ needed to push blood Pumping action creates _________ needed to push blood through vessels.through vessels.

Blood vessels:Blood vessels:► Permits blood flow from heart to cells and back to the heart.Permits blood flow from heart to cells and back to the heart.

Arteries, arterioles, capillaries, venules, veins.Arteries, arterioles, capillaries, venules, veins.

► Lymphatic System:Lymphatic System: Lymphatic vessels transport interstitial fluid.Lymphatic vessels transport interstitial fluid.

► Lymph nodes cleanse lymph prior to return in venous blood.Lymph nodes cleanse lymph prior to return in venous blood.

Composition of Blood Composition of Blood

►Plasma:Plasma: Straw-colored liquid.Straw-colored liquid.

►Consists of HConsists of H220 and dissolved solutes.0 and dissolved solutes. Ions, metabolites, hormones, antibodies.Ions, metabolites, hormones, antibodies.

► __________ is the major solute of the plasma.__________ is the major solute of the plasma.

►Plasma proteins:Plasma proteins: Constitute 7-9% of plasma.Constitute 7-9% of plasma.

►Albumin: Albumin: Accounts for 60-80% of plasma proteins.Accounts for 60-80% of plasma proteins. Provides the ______________________ needed to Provides the ______________________ needed to

draw Hdraw H220 from interstitial fluid to capillaries.0 from interstitial fluid to capillaries.► Maintains blood pressure.Maintains blood pressure.

► Plasma proteins (continued):Plasma proteins (continued): Globulins:Globulins:

►globulin:globulin: Transport _______ and ______ soluble vitamins.Transport _______ and ______ soluble vitamins.

►globulin: globulin: Transport lipids and fat soluble vitamins.Transport lipids and fat soluble vitamins.

►globulin: globulin: Antibodies that function in immunity.Antibodies that function in immunity.

► Fibrinogen:Fibrinogen: Constitutes 4% of plasma proteins.Constitutes 4% of plasma proteins. Important ___________factor.Important ___________factor.

► Converted into fibrin during the clotting process.Converted into fibrin during the clotting process.

Composition of the Blood Composition of the Blood (continued)(continued)

►Serum:Serum: Fluid from clotted blood.Fluid from clotted blood.

►Does not contain_________________.Does not contain_________________.

►Plasma volume:Plasma volume: Number of regulatory mechanisms in Number of regulatory mechanisms in

the body maintain homeostasis of the body maintain homeostasis of plasma volume.plasma volume.

►Osmoreceptors.Osmoreceptors.►ADH.ADH.►Renin-angiotensin-aldosterone system.Renin-angiotensin-aldosterone system.

Composition of the Blood Composition of the Blood (continued)(continued)

ErythrocytesErythrocytes

► Flattened biconcave discs.Flattened biconcave discs.► Provide increased surface area through Provide increased surface area through

which gas can diffuse.which gas can diffuse.► Lack Lack ______________________ and and ____________________________..

Half-life ~ ________ days.Half-life ~ ________ days.► Each RBC contains 280 million hemoglobin Each RBC contains 280 million hemoglobin

with 4 heme chains (contain iron).with 4 heme chains (contain iron).► Removed from circulation by Removed from circulation by phagocyticphagocytic

cells in cells in liverliver, , spleenspleen, and , and bone marrowbone marrow..

LeukocytesLeukocytes

► Contain nuclei and mitochondria. Contain nuclei and mitochondria. ► Move in amoeboid fashion.Move in amoeboid fashion.

Can squeeze through capillary walls (Can squeeze through capillary walls (________________).).

► Almost invisible, so named after their Almost invisible, so named after their staining properties.staining properties. Granular leukocytes:Granular leukocytes:

► Help detoxify foreign substances.Help detoxify foreign substances. Release heparin.Release heparin.

Agranular leukocytes:Agranular leukocytes:► Phagocytic.Phagocytic.

Produce antibodies.Produce antibodies.

Platelets (thrombocytes)Platelets (thrombocytes)

► Smallest of formed elements.Smallest of formed elements. Are fragments of megakaryocytes.Are fragments of megakaryocytes. Lack __________Lack __________

► Capable of amoeboid movement.Capable of amoeboid movement.► Important in blood clotting:Important in blood clotting:

Constitute most of the mass of the clot.Constitute most of the mass of the clot. Release _____________ to vasoconstrict and Release _____________ to vasoconstrict and

reduce blood flow to area.reduce blood flow to area.► Secrete growth factors:Secrete growth factors:

Maintain the integrity of blood vessel wall.Maintain the integrity of blood vessel wall.► Survive 5-9 days.Survive 5-9 days.

Blood Cells and PlateletsBlood Cells and Platelets

HematopoiesisHematopoiesis

► Undifferentiated cells gradually Undifferentiated cells gradually differentiate to become stem cells, differentiate to become stem cells, that form blood cells.that form blood cells.

► Occurs in myeloid tissue (bone marrow Occurs in myeloid tissue (bone marrow of long bones) and lymphoid tissue.of long bones) and lymphoid tissue.

► 2 types of hematopoiesis:2 types of hematopoiesis: Erythropoiesis:Erythropoiesis:

► __________________________________________ Leukopoiesis:Leukopoiesis:

► ____________________________.____________________________.

ErythropoiesisErythropoiesis

► Active process.Active process. _________ million RBCs are produced every second._________ million RBCs are produced every second.

► Primary regulator is Primary regulator is ____________________________________.. Binds to membrane receptors of cells that will become Binds to membrane receptors of cells that will become

erythroblastserythroblasts.. Erythroblasts transform into Erythroblasts transform into __________________________________.. Normoblasts lose their nuclei to become Normoblasts lose their nuclei to become reticulocytesreticulocytes.. Reticulocytes change into mature RBCs.Reticulocytes change into mature RBCs.

► Stimulates cell division. Stimulates cell division.

► Old RBCs are destroyed in Old RBCs are destroyed in ________________________ and and liverliver.. Iron recycled back to myeloid tissue to be reused in Iron recycled back to myeloid tissue to be reused in

hemoglobin production.hemoglobin production.

► Need iron, vitamin BNeed iron, vitamin B1212 and _____________ for synthesis. and _____________ for synthesis.

LeukopoiesisLeukopoiesis

► Cytokines stimulate different types and stages of Cytokines stimulate different types and stages of _________ production._________ production.

► Multipotent growth factor-1, interleukin-1, and Multipotent growth factor-1, interleukin-1, and interleukin-3:interleukin-3: Stimulate development of different types of Stimulate development of different types of

WBC cells.WBC cells.► Granulocyte-colony stimulating factor (G-CSF):Granulocyte-colony stimulating factor (G-CSF):

Stimulates development of neutrophils.Stimulates development of neutrophils.► Granulocyte-monocyte colony stimulating factor Granulocyte-monocyte colony stimulating factor

(GM-CSF):(GM-CSF): Simulates development of monocytes and Simulates development of monocytes and

eosinophils.eosinophils.

Blood ClottingBlood Clotting

►Function of platelets:Function of platelets: Platelets normally repelled away from Platelets normally repelled away from

endothelial lining by ____________ endothelial lining by ____________ (prostaglandin).(prostaglandin).

►Do not want to clot normal vessels.Do not want to clot normal vessels.

►Damage to the endothelium wall:Damage to the endothelium wall: Exposes subendothelial tissue to the Exposes subendothelial tissue to the

blood.blood.

Blood Clotting Blood Clotting (continued)(continued)

► Platelet release reaction:Platelet release reaction: Endothelial cells secrete Endothelial cells secrete __________________________________ to cause to cause

platelets to adhere to collagen.platelets to adhere to collagen. When platelets stick to collagen, they degranulate as When platelets stick to collagen, they degranulate as

platelet secretory granules:platelet secretory granules:► Release Release ADP, serotonin and thromboxane AADP, serotonin and thromboxane A22..

Serotonin and thromboxane ASerotonin and thromboxane A22 stimulate vasoconstriction. stimulate vasoconstriction. ADP and thromboxane AADP and thromboxane A22 make other platelets “sticky.” make other platelets “sticky.”

► Platelets adhere to collagen. Platelets adhere to collagen. ► Stimulates the platelet release reaction.Stimulates the platelet release reaction.

► Produce platelet plug.Produce platelet plug. Strengthened by activation of plasma clotting factors. Strengthened by activation of plasma clotting factors.

►Platelet plug strengthened by Platelet plug strengthened by __________.__________.

►Clot reaction:Clot reaction: Contraction of the platelet mass forms Contraction of the platelet mass forms

a more compact plug.a more compact plug. Conversion of fibrinogen to fibrin Conversion of fibrinogen to fibrin

occurs.occurs.

Blood Clotting Blood Clotting (continued)(continued)

Dissolution of ClotsDissolution of Clots

► Activated factor XII converts an inactive Activated factor XII converts an inactive molecule into the active form (____________). molecule into the active form (____________). Kallikrein converts plasminogen to plasmin.Kallikrein converts plasminogen to plasmin.

► PlasminPlasmin is an enzyme that digests the fibrin. is an enzyme that digests the fibrin. Clot dissolution occurs.Clot dissolution occurs.

► Anticoagulants:Anticoagulants: Heparin:Heparin:

► Activates ____________________.Activates ____________________. Coumarin:Coumarin:

► Inhibits cellular activation of __________________.Inhibits cellular activation of __________________.

Acid-Base Balance in the BloodAcid-Base Balance in the Blood

►Blood pH is maintained within a Blood pH is maintained within a narrow range by lungs and kidneys.narrow range by lungs and kidneys.

►Normal pH of blood is Normal pH of blood is 7.357.35 to to 7.457.45..►Some HSome H+ + is derived from is derived from

___________.___________.►HH220 + C00 + C02 2 HH22C0C03 3 HH++ + +

HC0HC033--

Buffer SystemsBuffer Systems

►Provide or remove ____ and stabilize Provide or remove ____ and stabilize the pH.the pH.

► Include weak acids that can donate Include weak acids that can donate ____ and weak bases that can absorb ____ and weak bases that can absorb HH++..

►_________ is the major buffer in the _________ is the major buffer in the plasma.plasma.

►Under normal conditions excessive HUnder normal conditions excessive H+ +

is eliminated in the urine.is eliminated in the urine.

Acid Base DisordersAcid Base Disorders

► Respiratory acidosis:Respiratory acidosis: Hypoventilation.Hypoventilation.

► Accumulation of COAccumulation of CO22.. ________________________________________________________

► Respiratory alkalosis:Respiratory alkalosis: Hyperventilation.Hyperventilation.

► Excessive loss of COExcessive loss of CO22.. ______________________________________________________

Acid Base DisordersAcid Base Disorders

►Metabolic acidosis:Metabolic acidosis: Gain of fixed acid or loss of HCO3-.Gain of fixed acid or loss of HCO3-.

►Plasma HCO3- decreases. Plasma HCO3- decreases. __________________________________________..

►Metabolic alkalosis:Metabolic alkalosis: Loss of fixed acid or gain of HCO3-.Loss of fixed acid or gain of HCO3-.

►Plasma HCO3- increases.Plasma HCO3- increases. ______________________________________________..

Pulmonary and Systemic Pulmonary and Systemic CirculationsCirculations

► Pulmonary circulation:Pulmonary circulation: Path of blood from right Path of blood from right

ventricle through the ventricle through the lungs and back to the lungs and back to the heart.heart.

► Systemic circulation:Systemic circulation: Oxygen-rich blood Oxygen-rich blood

pumped to all organ pumped to all organ systems to supply systems to supply nutrients.nutrients.

► Rate of blood flow Rate of blood flow through systemic through systemic circulation = flow rate circulation = flow rate through pulmonary through pulmonary circulation.circulation.

Atrioventricular and Semilunar Atrioventricular and Semilunar ValvesValves

► Atria and ventricles are separated into 2 Atria and ventricles are separated into 2 functional units by a sheet of connective functional units by a sheet of connective tissue by AV (atrioventricular) valves.tissue by AV (atrioventricular) valves. _______________ valves._______________ valves. Allow blood to flow from atria into the ventricles.Allow blood to flow from atria into the ventricles.

► At the origin of the pulmonary artery and At the origin of the pulmonary artery and aorta are semilunar valves.aorta are semilunar valves. One way valves.One way valves. Open during _____________contraction.Open during _____________contraction.

► Opening and closing of valves occur as a Opening and closing of valves occur as a result of ______________differences.result of ______________differences.

Atrioventricular and Semilunar Atrioventricular and Semilunar ValvesValves

Cardiac CycleCardiac Cycle► Refers to the repeating pattern of Refers to the repeating pattern of

contraction and relaxation of the contraction and relaxation of the heart.heart. Systole:Systole:

►Phase of _____________Phase of _____________ Diastole:Diastole:

►Phase of ________________Phase of ________________ End-diastolic volume (EDV):End-diastolic volume (EDV):

► Total volume of blood in the ventricles at the Total volume of blood in the ventricles at the end of diastole.end of diastole.

Stroke volume (SV):Stroke volume (SV):► Amount of blood ejected from ventricles during Amount of blood ejected from ventricles during

systole.systole. End-systolic volume (ESV):End-systolic volume (ESV):

► Amount of blood left in the ventricles at the Amount of blood left in the ventricles at the end of systole.end of systole.

Heart SoundsHeart Sounds

► Closing of the AV and Closing of the AV and semilunar valves.semilunar valves.

► Lub (first sound):Lub (first sound): Produced by closing of Produced by closing of

the AV valves during the AV valves during isovolumetric isovolumetric contraction.contraction.

► Dub (second sound):Dub (second sound): Produced by closing of Produced by closing of

the semilunar valves the semilunar valves when pressure in the when pressure in the ventricles falls below ventricles falls below pressure in the pressure in the arteries.arteries.

Conducting Tissues of the HeartConducting Tissues of the Heart

► APs spread through myocardial cells APs spread through myocardial cells through gap junctions.through gap junctions.

► Impulses cannot spread to ventricles Impulses cannot spread to ventricles directly because of fibrous tissue.directly because of fibrous tissue.

► Conduction pathway:Conduction pathway: SA node.SA node. AV node.AV node. Bundle of _______________Bundle of _______________ Purkinje fibers.Purkinje fibers.

► Stimulation of Purkinje fibers cause both Stimulation of Purkinje fibers cause both ventricles to contract simultaneously.ventricles to contract simultaneously.

Conducting Tissues of the Heart Conducting Tissues of the Heart (continued)(continued)

Blood VesselsBlood Vessels

►Walls composed of 3 “tunics:”Walls composed of 3 “tunics:” Tunica _______________:Tunica _______________:

►Outer layer comprised of connective tissue.Outer layer comprised of connective tissue.

Tunica ______________:Tunica ______________:►Middle layer composed of smooth muscle.Middle layer composed of smooth muscle.

Tunica _______________:Tunica _______________:►Innermost simple squamous endothelium.Innermost simple squamous endothelium.►Basement membrane.Basement membrane.►Layer of elastin.Layer of elastin.

Blood VesselsBlood Vessels

► Most of the blood volume is contained in the Most of the blood volume is contained in the venous system.venous system. Venules:Venules:

► Formed when ________________.Formed when ________________. Very porous.Very porous.

Veins: Veins: ► Contain little smooth muscle or elastin.Contain little smooth muscle or elastin.

Capacitance vessels (_________________).Capacitance vessels (_________________).► Contain 1-way valves that ensure blood flow to the heart.Contain 1-way valves that ensure blood flow to the heart.

► Skeletal muscle pump and contraction of Skeletal muscle pump and contraction of diaphragm:diaphragm: Aid in venous blood return of blood to the heart.Aid in venous blood return of blood to the heart.

Types of CapillariesTypes of Capillaries

► Capillaries:Capillaries: Smallest blood vessels.Smallest blood vessels.

► 1 endothelial cell thick.1 endothelial cell thick. Provide direct access to cells.Provide direct access to cells.

► Permits exchange of nutrients and wastes. Permits exchange of nutrients and wastes.

Lymphatic SystemLymphatic System

►3 basic functions:3 basic functions: Transports interstitial (tissue) fluid back to Transports interstitial (tissue) fluid back to

the blood.the blood. Transports absorbed fat from small Transports absorbed fat from small

intestine to the blood.intestine to the blood. Helps provide immunological defenses Helps provide immunological defenses

against pathogens.against pathogens.

Lymphatic System Lymphatic System (continued)(continued)

► Lymphatic capillaries:Lymphatic capillaries: Closed-end tubules that Closed-end tubules that

form vast networks in form vast networks in intercellular spaces.intercellular spaces.

► Lymph:Lymph: Fluid that enters the Fluid that enters the

lymphatic capillaries.lymphatic capillaries.► Lymph carried from Lymph carried from

lymph capillaries, to lymph capillaries, to lymph ducts, and then lymph ducts, and then to lymph nodes.to lymph nodes.

Lymph nodes filter the Lymph nodes filter the lymph before returning lymph before returning it to the veins. it to the veins.