Lecture Exam 2 Flashcards
Non-living fluid matrix of blood.
Plasma
3 Formed Elements of Blood
Platelets, Erythrocytes, Leukocytes
Red Blood Cells are Called:
Erythrocytes
White Blood Cells are called:
Leukocytes
3 Layers of Blood when spun in a centrifuge
Plasma, Buffy Coat (WBC/Platelets), Erythrocytes
Plasma should make up how much of a hematocrit?
55%
Erythrocytes should make up how much of a hematocrit?
45%
How do you figure out how much of an element in a hematocrit?
Column of element/column of whole tube multiplied by 100
Function of Leukocytes
Protect body from bacteria, viruses, parasites, toxins, and tumor cells.
Diapedisis
The way that WBC’s leave the capillaries towards infection using ameboid motion and positive chemotaxis
Leukocytosis
Increased production of WBC’s, normal response to infection.
3 Granulocytes
Neutrophils, Eosinophils, Basophils
2 Agranulocytes
Lymphocytes, Monocytes
Most common Leukocytes to Least Common
Neutrophils, Lymphocytes, Monocytes, Eosinophils, Basophils
Characteristics of Granulocytes
Cytoplasmic granules, shorter lived that RBC’s, Lobed nuclei, all phagocytic.
Characteristics of Neutrophils
Most abundant, 3-6 lobes in nucleus, Larger than RBC’s, contain defensins, phagocytize bacteria
Characteristics of Eosinophils
Bi-lobed nucleus, Red granules, Larger than RBC’s, Defend against parasitic worms, Role in allergies and asthma
Characteristics of Basophils
Deep Purple nucleus, Larger than RBC’s, Least abundant, contain histamine
Histamine
Inflammatory chemical that dilates blood vessels to attract WBC’s to site of infection.
Characteristics of Lymphocytes
Deep purple, circular nuclei, Mostly in lymphoid tissue, Mount immune response
Characteristics of Monocytes
Kidney shaped nuclei, very large.
Function of Monocytes
Differentiate into microphages and enter tissues, actively phagocytic, activate lymphocytes to mount immune response.
Leukopoiesis
Production of WBC’s.
Leukopoiesis is stimulated by:
Interleukins and Colony Stimulating Factors
All leukocytes originate from:
Hemocytoblasts
Where are the chemical messengers found that stimulate Leukopoiesis?
Red Bone Marrow and Mature WBC’s
Leukopenia
Abnormally low WBC count.
What causes Leukopenia?
Glucocorticoids or anti-cancer drugs
What is Leukemia?
The Cancerous overproduction of abnormal WBC’s. Fill red bone marrow .
Myeloid Leukemia
Myoblast decendents (granulocytes)
Lymphocytic Leukemia
Involves lymphocytes
Acute Leukemia
Derives from Stem Cells
Chronic Leukemia
Derives from later cell stages.
Infectious Mononucleosis
Excessive numbers of atypical a granulocytes. Caused by Epstein Barr Virus
Symptoms of Infectious Mononucleosis
Tired, achy, sore throat, low fever
How do you treat infectious mononucleosis
Runs course with rest
Sickle Cell Anemia
Red Blood Cells are sickle shaped, not round. Rupture easily and block small vessels.
Pernicious Anemia
Large and Odd Shaped RBC’s
Whole Blood Transfusions
Used when blood loss is rapid and substantial (>30%).
Packed Red Cell Transfusions
Transfused in other cases, restore Oxygen carrying capacity.
Loss of ______ or more blood can be fatal.
30%
Transfusions of incompatible blood can be _________.
Fatal
Antigens (Agglutinogens)
Generate Immune Response
Antibodies (Agglutinins)
Pre-formed Anti-A or Anti-B antibodies
Type A blood would have:
Antigens: A Antibodies: Anti-B
Type B blood would have:
Antigens: B Antibodies: Anti-A
Type AB blood would have:
Antigens: A and B Antibodies: None
Type O blood would have:
Antigens: None Antibodies: Anti-A and Anti-B
Which type of blood is a universal donor?
Type O
Which type of blood is a universal receiver?
Type AB
Agglutinated
Clumped together
If someone’s blood type is O negative, what antigen are they missing?
RH antigen
How many times does someone who is RH- have to be transfused with RH+ blood to get a reaction.
The second time there is a reaction.
Someone will only produce RH antibodies if:
A mom is carrying an RH+ baby, and individual who is RH- receives RH+ blood.
Erythroblastosis Fetalis
When an RH- mom is carrying an RH+ baby, the second time the baby may become anemic or hypoxic.
RhoGRAM Serum
Contains artificial RH antibodies so that the mother of a baby doesn’t produce RH antibodies and attacks the fetus.
Results of Transfusion Reactions
Diminished O carrying capacity, Diminished blood flow beyond blocked vessels, Ruptured cells release hemoglobin and cause kidney failure.
Treatment for transfusion reactions
Fluids and diuretics to wash out hemoglobin.
Low Blood Volume can cause_____ and_____.
Shock and Death
3 Functions of Blood:
Distribution, Regulation, Protection
Blood Distribution:
Distributes O, Nutrients, Hormones. Removes metabolic waste.
Blood Regulation:
Maintains body temperature, pH, Fluid volume
Lower blood pH than normal:
Acidosis
Higher blood pH than normal:
Alkalosis
Blood Protection:
Provides Leukocytes
Plasma
Non-living fluid matrix of blood
Blood Plasma Characteristics
90% Water, Least heavy layer and the most abundant, Solutes
Solutes of Blood Plasma
Electrolytes and Plasma Proteins (albumin)
Albumin
Regulates osmotic pressure
Function of Erythrocytes
Respiratory gas transport
Hemoglobin
Binds reversibly with Oxygen
Characteristics of Erythrocytes
Small, biconcave, high hemoglobin content, no mitochondria, aneucleate
Globin
Composed of 4 polypeptide chains
Heme
Pigment bonded to each globin chain. Iron atom binds with 1 Oxygen atom.
How many O atoms can each Hb (Hemoglobin) molecule bind to?
4
Oxyhemoglobin
Produced by O2 loading into lungs. Ruby red in color.
Deoxyhemoglobin
Produced by O2 unloading in tissues. Dark red in color.
Carbaminohemoglobin
Produced when CO2 loads in tissues. 20% of CO2 in blood binds to Hb.
Hematopoiesis
Production of blood cells
Blood cell formation occurs where?
Red bone marrow
Erythropoesis
Production of Red Blood Cells
All blood cells arise from a ____________.
Hemocytoblast
Hormones and growth factors influence ___________ to turn into erythrocytes.
Myeloid Stem Cells
Balance of RBC production and destruction depends on:
Hormonal Controls and Dietary requirements
Too few RBC’s leads to_______
Tissue Hypoxia
Too many RBC’s leads to ________
Blood viscosity
Erythropoietin (EPO)
Glycoprotein hormone in kidneys that stimulates RBC production.
EPO production is increased by ______.
Hypoxia
EPO is increased by hypoxia due to:
Decreased RBC’s, Insufficient Hemoglobin, Reduced O availability
Dietary Requirements for Erythropoesis
Nutrients and structural materials, Iron, B complex vitamins
What element is necessary for hemoglobin synthesis?
Iron
What type of vitamins are necessary for DNA synthesis?
B complex vitamins (Folic, B12)
How long does an RBC live in the bloodstream?
About 100 days
What happens to the parts of RBC’s that cannot be reused?
Excrete them
What part of the RBC must be reused?
Hemoglobin
When an RBC is destroyed Heme is taken where?
Fe goes back to the blood stream, the rest is taken to the liver.
When an RBC is destroyed Globin is taken where?
It is turned into amino acids
Anemia
Bloods Oxygen carrying capacity is too low to support normal metabolism
Polycythemia
Abnormal excess of erythrocytes
Symptoms of Anemia
Fatigue, pallor, shortness of breath, chills
Causes of Anemia
Blood loss, Low RBC production, High RBC destruction
Acute Hemmorhagic Anemia
Rapid loss of blood quickly
Chronic Hemmorhagic Anemia
Slight, but persistent blood loss
Iron deficiency anemia
Caused by hemmorhagic anemia, low iron intake or impaired absorption
Pernicious Anemia Causes
Autoimmune Disease, Lack of ability to absorb B12 to have cell division.
Renal Anemia
Lack of Erythropoeitin
Aplastic Anemia
Destruction or inhibition of red bone marrow by chemicals, drugs, radiation or viruses
Hemolytic Anemias
Premature RBC lysis
Thalassemias
Where one globin chain is absent or faulty
Sickle Cell Anemia occurs mostly in what race of people?
Black/African
You have a better chance of surviving malaria if you have how many copies of the sickle cell gene?
One
If you have one copy of the sickle cell gene you have ________ if you have two copies you have ________.
Sickle Cell Trait, Sickle Cell Anemia
Polycythemia Vera
Bone Marrow Cancer
Secondary Polycythemia
Less O2 available (high altitude) or EPO production increases.
Blood Doping
Artificially induced polycythemia to increase O2 carrying capacity. Used by athletes.
Function of Platelets
Clotting Process, Form temporary plug to help seal breaks in vessel walls.
Why is blood doping dangerous?
Blood can become too viscous
Platelets are made from:
Ruptured cytoplasmic elements of a megakarocyte.
What hormone regulates the formation of platelets?
Thrombopoieten
Hemostasis
3 reactions that help prevent the loss of blood from breaks in the vessel walls.
Hemostasis is _______, ________, and _________
Fast, localized, and highly controlled
What coordinates Hemostasis?
Clotting Factors
3 Steps to Hemostasis
Vascular Spasm, Platelet Plug Formation, Coagulation of Blood
Vascular Spasm
Damaged blood vessel responds to injury by constricting.
Vasoconstriction
The constriction of a blood vessel
Triggers of a Vascular Spasm
Direct injury to blood vessel wall, Chemicals released by endothelial cells and platelets, Local pain receptor reflexes
von Willebrand Factor
Plasma protein that helps platelets stick to collagen fibers.
Damage to blood vessel exposes ___________
Collagen fibers
Platelets release _________ to make nearby platelets to become spiked and sticky.
Chemical messengers
Chemical Messengers that cause platelets to become sticky
Adenosinediphosphate (ADP), Serotonin, Thromboxane A2
In coagulation, platelet plug is reinforced with _________.
Fibrin Threads
In coagulation blood is formed from ______ to _______.
Liquid to gel
3 phases of coagulation:
Prothrombin activator formed, Prothrombin turns into thrombin, Thrombin catalyzes fibrinogen to fibrin
Factor __ works to form the prothrombin activator
X
Coagulation phase 1
Factor X works to form prothrombin activator
Coagulation phase 2
Prothrombin activator catalyzes transformation of prothrombin to thrombin
Coagulation phase 3
Thrombin catalyzes the transformation of fibrinogen to fibrin.
Fibrinogen is _________ while fibrin is ________
soluble, insoluble
Thrombin also activates factor _________ or __________.
Factor XIII, Fibrin stabilizing factor
Clot retraction
Platelets contract, drawing edges of ruptured blood vessels together.
Vessel Healing
Stimulates cells of vessel walls to divide
Platelets release __________ for vessel healing
Platelet Derived Growth Factor (PDGF)
Endothelial cells release ________ for vessel healing
Vascular Endothelial Growth Factor (VEGF)
Fibrinolysis
Removes unneeded clots after healing
Plasmin
Fibrin-digesting enzyme
Homeostatic Mechanisms limiting clot growth
Removal of clotting factors, Inhibition of activated clotting factors
Antithrombin III
Inactivates thrombin
Heparin
Enhances Antithrombin III
Thromboembolic Disorders
Undesirable clot formation
Bleeding Disorders
Unable to clot
Disseminated Intravascular Coagulation (DIC)
Clotting and Bleeding issues
Thrombus
Stationary clot that develops and persists in an unbroken vessel
Thrombosis
Formation of a blood clot inside a vessel that blocks the flow of blood.
Embolus
A Thrombus that is freely floating throughout the body
Embolism
Stuck clot
4 Anticoagulant Drugs
Aspirin, Heparin, Warfarin, Dabigitran
Aspirin
Inhibits Thromboxane A2
Warfarin (Coumadin)
Interferes with Vitamin K production of clotting factors
Dabigitran
Inhibits thrombin
2 Causes of Deficient Clotting
Circulating platelet deficiency, Deficiency of clotting factors
Thrombocytopenia
Platelet Deficiency
Circulating platelet deficiency can come from ________
Red bone marrow destruction
Deficiency of Clotting factors can come from________
Impaired liver function, Vitamin K deficiency, Hepititis or Cirrohsis
Hemophilia
A genetic disease, Factor VIII, Minor tissue trauma causes prolonged bleeding
Hemophilia ____ is the most common type
A
Disseminated Intravascular Coagulation (DIC)
Clotting in intact blood vessels, severe bleeding because residual blood unable to clot.
DIC can happen because of
Pregnancy issues, Septicemia, Incompatible Blood Transfusions
Coordinated Heartbeat is a function of _____ and _____
Gap junctions, Intrinsic conduction system
Cardiac Pacemaker Cells
Noncontractile cells with unstable resting membrane potential
Cardiac Pacemaker Cells do two things:
Drift toward depolarization, Trigger rhythmic contractions through action potentials
3 parts of Action Potential
Pacemaker Potential, Depolarization, Repolarization
Electrical Impulse of the Heart Passes in this order:
SA node, AV note, Bundles of His, Purkinje Fibers (Subendocardial Conducting Network)
Sino Atrial Node
Drives Heart Rate, Generates the impulse.
Atrioventricular Node
Impulse Pauses here
Atrioventricular Bundle
Connects Atria to the Ventricles
Bundle Branches
Conduct impulses through the inter ventricular septum
Subendocardial Conducting Network
Depolarizes contractile cells of both ventricles
SA node has ______ bpm
75
AV node has ______ bpm
50
AV bundle and Purkinje Fibers have _____ bpm
30
Arrythmias
Irregular Heart Rhythms
Fibrillation
Rapid, irregular contractions
Defibrillation
Resetting the electrical activity of the heart
Homeostatic Imbalances of the Electrical System of the Heart
Arrhythmias, Fibrillation, Uncoordinated atrial and ventricular contractions
Ectopic Focus
Abnormal pacemaker caused by defects with SA node. AV node sets a junctional rhythm (45-60bpm)
Extrasystole
Premature contraction. Can be caused by nicotine or caffeine
Heart Block
Few or no impulses reach ventricles because of defective AV node. Too slow for life, need artificial pacemaker to treat.
Extrinsic Innervation of the Heart:
Heartbeat modified by ANS via cardiac centers in the brainstem.
Cardioacceleratory Center
Sympathetic, accelerates via AV, SA nodes, heart muscle and coronary arteries.
Cardioinhibitory Center
Parasympathetic, inhibits via AV, SA nodes
ECG
Electrocardiogram, composite of all action potentials generated by nodal and contractile cells of the heart
3 deflections of an ECG
P wave, QRS Complex, T wave
P Wave
Movement of depolarization wave from SA node through atria.
QRS complex
Ventricular depolarization and atrial repolarization
T wave
Ventricular repolarization
P-R interval
Beginning of atrial excitation to beginning of ventricular excitation
S-T segment
Entire ventricular myocardium depolarized
Q-T interval
Beginning of ventricular depolarization through ventricular repolarization
Junctional Rhythm
SA node is non-functional, P waves are absent. AV node paces heart between 45-60 bpm
Second Degree Heart Block
More P than QRS waves are seen. P waves repeat themselves.
Ventricular Fibrillation
Chaotic and irregular ECG
Right side of the heart picks up what kind of blood from where?
Deoxygenated from the tissues
Pulmonary Circuit
Blood pumped into the lungs to receive O2
Left side of the heart picks up what kind of blood from where?
Oxygenated from the lungs
Systemic Circuit
Blood pumped to the tissues from the lungs.
The heart is located in which part of the thoracic cavity?
Mediastinum
Base of the heart leans where?
Toward the right shoulder
Apex of the heart points where?
Left hip
Pericardium
Double Walled sac enclosing heart
Fibrous Pericardium
The superficial layer of the pericardium
Parietal Serous Pericardium
Lines internal surface of fibrous pericardium
Visceral Serous Pericardium (epicardium)
On the external surface of the heart
Myocardium
Spiral bundles of contractile cardiac muscle cells, Connective tissue of cardiac skeleton
Endocardium
Continuous with endothelial lining of blood vessels
Atria
Superior chambers, receiving chambers
Ventricles
Inferior Chambers, Discharging chambers
Interatrial Septum
Separates atria
Interventricular Septum
Separates ventricles
Valves of the heart
Ensure uni-directional flow of blood, Open and close in response to pressure changes
Tricuspid Valve
Right atrioventricular valve
Bicuspid (mitrial) Valve
Left atrioventricular valve
Chordae Tendinae
Collagenous chords anchor cusps of valves to papillary muscles on ventricle walls
AV Valves open when ________ pressure is greater than ________ pressure
Atrial, Ventricular
AV valves close when _________ pressure is greater than _______ pressure.
Ventricular, Atrial
Semilunar valves
Prevent back flow of blood into ventricles
Incompetent Valve
Blood back flows and heart repumps same blood over and over.
Valvular Stenosis
Stiff flaps of valves constrict opening heart exerts more force to pump blood.
Coronary Circulation
Functional blood supply to heart itself
Blood is delivered to the coronary circulation when:
The heart is relaxed
The ________ receives the most blood supply
Left Ventricle
Arteries arise from the ________
Aorta
Cardiac Veins
Collect blood from capillary beds
Angina Pectoris
Chest pain caused by deficiency in blood delivery to myocardium, cells weakened.
Myocardial Infarction
Heart Attack, Prolonged coronary blockage, Areas of cell death repaired with non contractile scar tissue
Which circuit is short?
Pulmonary Circuit
Which circuit is long?
Systemic Circuit
Pulmonary circuit has ______ pressure.
Low
Systemic Circuit has _________ friction.
High
The left ventricle walls are ________ than the right.
3x thicker
Cardiac muscles are ________, ________, and have many _______.
Branched, Striated, Mitochondria
Sarcolemma
Plasma membrane of a muscle fiber
T Tubule
Infolding of the sarcoma that helps in communication with organelles
Sarcoplasm
cytoplasm of a muscle cell
Sarcoplasmic Reticulum
Specialized smooth E.R. Stores intracellular calcium
Myofilaments
Fibers that slide past each other when muscle contracts
Intercalated Disks
Junctions between cardiac cells
Desmosomes
Prevent cells from separating during contraction
Gap Junctions
Allow ions to pass from cell to cell
Functional Syncytium
Coordinated Unit
______ and _____ allow the heart to be a functional syncytium.
Desmosomes and gap junctions
Automaticity
Self-excitable cells.
What kind of cells generate depolarization?
Non-Contractile cells
Organ Contraction of the Heart
All contractile cells contract as a unit or none do
Long Absolute Refractory Period
Prevents wave summation and tetanus which would stop the pumping action of the heart.
Sequence of Events that happen during a Muscle Contraction (Cellular Level)
Na channels open with depolarization, Na enters sarcoplasm, Depolarization of membrane opens other Na channels, Na channels close rapidly, Sarcoplasmic reticulum releases Ca, Ca signals muscle filaments to perform a muscle contraction.
3 Phases of Cardiac Muscle Contraction
Depolarization, Plateau, Repolarization
What happens during the Depolarization phase?
Na influx, positive feedback opens more Na channels, Channels close.
What happens during the Plateau phase?
Slow Ca influx keeps the cell depolarized
What happens during the Repolarization phase?
Ca channels close and K channels open repolarizing the cell membrane. This requires ATP and uses the NaK pump.
A ligand channel is where?
Around the sarcoplasmic reticulum.
How many Na can the NaK pump hold?
3
How many K can the NaK pump hold?
2
Cardiac muscle has much more _______ than skeletal muscle.
Mitochondria
Fuel Sources for Cardiac Muscle
Glucose, fatty acid, lactic acid
The heart has a great dependence on __________ respiration.
Aerobic
The heart has little ________ respiration ability.
Anaerobic
Two Sounds Associated with the Heart:
Lub and Dup
What happens during the Lub sound in the heart?
AV valves close, beginning of systole
What happens during the Dup sound in the heart?
SL valves close, beginning of ventricular diastole
What happens between the Lub and Dup sounds?
There is a pause where the heart relaxes.
Heart Murmur
Abnormal heart sounds, usually indicates incompetent or stenotic valve
Cardiac Cycle
All events associated with the blood flow during one complete heartbeat.
3 phases of the cardiac cycle
Ventricular filling, Ventricular Systole, Isometric relaxation
What happens during phase 1 of the cardiac cycle?
Ventricular Filling: AV valves open, Blood passively flows into low pressure ventricles. Atrial systole leads to end diastolic volume.
End Diastolic Volume (EDV)
Max volume of blood that ventricles will contain during the cardiac cycle
What happens during phase 2 of the cardiac cycle?
Ventricular Systole: Atria relax, ventricles contract, rise in ventricular pressure leads to AV valves closing, Ejection phase: ventricular pressure greater than that of arteries, SL valves open, leads to end systolic volume.
Ejection Phase
Ventricular pressure is greater than that of large arteries, so SL valves open.
End Systolic Volume (ESV)
Amount of blood remaining in each ventricle after systole.
Isovolumetric Contraction Phase
When all valves are closed
What happens during phase 3 of the cardiac cycle?
Isometric Relaxation: Ventricles relax, atria filling, Backflow of blood closes SL valves, When atrial pressure exceeds ventricular pressure, AV valves open.
Dicrotic notch
Brief rise in aortic pressure from blood bouncing off closed valve.
Cardiac Output
Volume of blood pumped by each ventricle in one minute.
The equation for cardiac output
CO=HRxSV
Heart Rate
Number of beats per minute
Stroke Volume
Volume of blood pumped out by one ventricle in each beat.
Cardiac Output is measured in:
Milliliters per minute
Cardiac Reserve
Difference between maximal and resting CO. Dependent on cardiovascular health, highly variable among individuals
Equation to find Stroke Volume
SV=EDV-ESV
EDV is affected by:
Length of ventricular diastole, venous pressure
ESV is affected by:
Arterial BP, force of ventricular contraction
3 main factors that affect Stroke Volume
Preload, Contractility, Afterload
Preload
Degree of stretch of cardiac muscle before they contract.
Frank-Starling Law of the Heart
Stroke volume of blood stretches fibers in the heart and makes cardiac muscle contract more forcefully.
At rest muscles are ______ than optimal length.
Shorter
Venous return
Amount of blood returning to the heart
Most important factor stretching cardiac muscle is:
Venous Return
Venous Return is increased by:
Slow Heartbeat, Exercise
Increased Venous Return ______ ventricles and ______ contraction force
Stretches, Increases
Contractility
Contractile strength at given muscle length
Increased Contractility is because of these two factors:
Sympathetic Stimulation, Positive inotropic agents
Positive Inotropic Agents
Epinephrine, High extracellular Ca, Thyroxine
Negative Inotropic Agents
Acidocis, Increased extracellular K, Ca channel blockers
Decreased Contractility is because of one factor:
Negative Inotropic Agents
Afterload
Pressure ventricles must overcome to eject blood.
Hypertension
High Blood Pressure
Hypertension increases _________, resulting in increased ________ and decreased ________.
Afterload, ESV, SV
Positive Chronotropic Factors
Increase Heart Rate
Negative Chronotropic Factors
Decrease Heart Rate
When blood volume drops and heart is weakened, how does this affect the SV, CO, and HR?
SV drops, CO is maintained by increasing HR.
Sympathetic Nervous System
Nervous system activated by physical or emotional stressors.
Norepinephrine
Causes pacemaker to fire more rapidly, increases contractility, faster relaxation
Parasympathetic Nervous System
Opposes sympathetic nervous system, recovery.
Acetylcholine
Hyper-polarizes pacemaker cells by opening K channels.
Vagal Tone
Parasympathetic Nervous System is dominant
Chemical Regulation of Heart Rate
Hormones, Ion Concentrations
Epinephrine
Increases heart rate and contractility
Thyroxine
Increases heart rate and enhances epinephrine
Hypocalcemia
Low Calcium, Depresses Heart Rate
Hypercalcemia
High Calcium, Increased HR and Contractility
Hyperkalemia
High Potassium, Alters electrical activity, Heart block and Cardiac Arrest
Hypokalemia
Low Potassium, Feeble heartbeat, Arrythmias
Other Factors that influence Heart Rate
Age, Gender, Exercise, Body Temperature
HR _______ when body temperature increases
Increases
What has the fastest Heart Rate?
Fetus
What gender has the faster Heart Rate?
Females
Tachycardia
Heart Rate Faster than 100bpm, may lead to fibrillation
Bradycardia
Heart rate slower than 60bpm, inadequate blood circulation in non-athletes.
Congestive Heart Failure (CHF)
CO so low that circulation is inadequate to meet tissue needs.
What causes Congestive Heart Failure?
Coronary Athersclerosis, Hypertension, Multiple Myocardial infarctions, Dialated Cardiomyopathy
Coronary Athersclerosis
Clogged vessels
Dialated Cardiomyopathy (DCM)
Ventricles stretch and doesn’t allow them to contract efficiently.
Pulmonary Congestions
Left Side fails, blood appears in lungs.
Peripheral Congestion
Right Side fails, blood pools in body tissues/edema
Edema
Blood pooling in body tissues
Human heart begins as _____ instead of 4 chambered heart
2 endothelial tubes
2 Structures that bypass pulmonary circulation
Foramen Ovale, Ductus Arteriosus
Foramen Ovale
Connects the 2 atria, bypass right ventricle to the lungs, becomes fossa ovalis
Ductus Arteriosus
Connects Pulmonary Trunk and Aorta, becomes Ligamentum Arteriosum
Arteries
Carrying blood away from the heart
Capillaries
Contact tissues, give oxygen and nutrients, exchange of materials
Veins
Carry blood back towards the heart
Tunica Intima
Endothelium lines lumen of all vessels, slick surface reduces friction
Tunica Media
Smooth muscle and sheets of elastin, Thicker in arteries, influence bloodflow and pressure
Tunica Externa
Thicker in veins, Collagen fibers protect and anchor to surrounding fibers
Arterial Vessels from largest to smallest
Elastic Arteries, Muscular Arteries, Arterioles
Elastic Arteries
Large, thick-walled arteries closest to the heart, Large lumen=low resistance, low pressure down stream
Muscular Arteries
Distal to elastic arteries, Delivery system to organs, Thick tunica media, active in vasoconstriction
Arterioles
Smalles arteries, Control flow into capillary beds
Flow of blood through the arterial system
Heart, Elastic Arteries, Muscular Arteries, Arterioles, Capillaries
Capillaries
Microscopic Vessels, Walls are tunica intima only, Exchange of gasses, nutrients, waste between blood and interstitial fluid.
Capillaries from Most to Least Permeable
Sinusoid, Fenestrated, Continuous
Continuous Capillary
Least permeable, most common, found in skin and muscle, Allows fluids and some small solutes
Fenestrated Capillary
Large fenestrations, increased permeability, larger particles, in areas of absorption In the kidney, and small intestine.
Sinusoid Capillary
Most Permeable, Large intercellular clefts, allow blood cells and large particles. Found in bone marrow, liver, spleen
Capillary Beds
Interwoven networks of capillaries that control blood to arterioles and venules.
Flow through the capillary bed:
Terminal Arteriole, Meta arteriole, Thoroghfare Channel, Post capillary venule
Two types of capillary blood vessels
Vascular Shunt, True Capillaries
Vascular Shunt
Directly connects terminal arteriole and Post Capillary Venule
True Capillaries
Branch of Meta or Terminal Arterioles
Precapillary Sphincters
Regulates blood flow through capillary bed
Venules
Formed when capillary beds unite, very porous
Veins
Form when venules converge, have thinner walls and larger lumens than arteries, Blood pressure lower than arteries
Veins hold ______ % of the blood volume
60%
Veins have 2 adaptations that help blood get back to the heart:
Venous Valves, Venous Sinuses
Venous Valves
Force blood to flow in an unidirectional manner
Venous Sinuses
Like a funnel that force blood in a unidirectional manner
Vascular Anastomoses
Interconnection of blood vessels. Alternative channels.
What Anastomoses are more common, Arterial or Venous?
Venous
Blood Flow
(ml/min) Volume of blood flowing through something in a period of time
Blood Pressure
(mm/Hg) Force per unit area exerted on blood vessel wall by blood
Resistance
Measure of friction blood encounters with vessel walls, generally in systemic circuit.
3 Sources of Resistance
Blood Viscosity, Vessel Length, Vessel Diameter
Blood Viscosity
Stickiness, controlled by formed elements
We have the most control over what source of resistance?
Vessel Diameter
Blood flow is directly proportional to _________
Pressure
Blood flow is inversely proportional to ________
Resistance
Equation for Flow
F=Pressure/Resistance
Arterial Blood Pressure: 2 factors
Elasticity, Volume of blood forced into arteries
Systolic Pressure
Pressure exerted into the aorta. Highest pressure 120mm/Hg
Diastolic Pressure
Lowest Level of aortic pressure 70-80mm/Hg
Pulse Pressure
Difference between Systolic and Diastolic Pressure
Mean Arterial Pressure (MAP)
Pressure that propels blood to tissues
Equation to find MAP
MAP=Diastolic+(Pulse/3)
Capillary Blood Pressure
Low pressure is desirable, High BP would rupture walls, Low Pressure forces filtrate into interstitial spaces
Venous Blood Pressure
Changes little during cardiac cycle, Low pressure due to peripheral resistance
Factors that Aid Venous Return
Muscular Pump, Respiratory Pump, Sympathetic Vasocontriction
Muscular Pump
Skeletal muscles put blood towards the heart and prevent backflow
Respiratory Pump
Pressure changes during breathing, pumps blood towards the heart
Sympathetic Vasoconstriction
Constrict venous vessels
Main Factors influencing blood pressure
Cardiac Output, Peripheral Resistance, Blood Volume
Equation for Pressure
P =COxR
Two Controls used during short term regulation of blood pressure
Neural and Hormonal Controls
Long Term Regulation of blood pressure is usually because of __________
Renal Regulation
Neural Control of Blood Pressure Regulation
Cardiovascular Center
Cardiovascular Center
Clusters of sympathetic neurons in brain stem oversee changes in CO and diameter
2 Parts of the Cardiovascular Center
Cardiac Center, Vasomotor Center
Cardiac Center
Cardioacceleratory Center and Cardioinhibitory Center, HR Control
Vasomotor Center
Sends steady impulses to control diameter of vessels
Reflex Arcs
Alter CO and R
Types of Reflex Arcs
Baroreceptor, Chemoreceptor, Higher Brain Centers
Baroreceptors
Aortic Arch, measures pressure, found in major neck arteries as well
Chemoreceptors
Aortic Arch and major neck arteries, respond to chemical signals, respond to levels of CO2, pH, O2
Types of Higher Brain Centers
Cerebral Cortex, Hypothalamus, Medulla Oblongata
Short Term Hormonal Controls regulate:
Peripheral Resistance
Short Term Neural Controls alter:
Peripheral Resistance and Cardiac Output
Epinepherine, Norepinephrine increase
Vasoconstriction
Kidneys sense blood pressure and generate this hormone:
Angiotensin II
Angiotensin II increases
Vasoconstriction
Antidiuretic Hormone (ADH) increases
Vasoconstriction
Atrial Natriuretic Peptide (ANP) increases
Vasodialation
ANP comes from which part of the body
The heart
Long Term Controls alter __________ via ______
Blood Volume via Kidneys
Direct Renal Mechanism
Alters blood volume independently, if increased BP increased filtration and excretion, and vice versa.
Indirect Renal Mechanism
Hormonal Controls, Angiotensin II, increases blood volume to increase BP by retaining salt and reducing urination
Tissue Perfusion
Delivery of O2 and nutrients, removal of waste from tissue cells.
Velocity of Blood Flow
High Velocity through arterial side, slows at capillaries (proper exchange), picks up through venous system
Autoregulation
Automatic adjustment of blood flow to each tissue relative to it’s requirements
2 Short Term Regulation Strategies
Metabolic Controls, Myogenic Controls
Metabolic Controls of Autoregulation
Maintenance of waste, Increases blood flow if build up of waste.
Myogenic Controls of Autoregulation
Maintenance of pressure into capillaries. Smooth muscle cells in vessels stretch
Long Term Autoregulation
Angiogenesis
Angiogenesis
of vessels to region increases and existing vessels enlarge
Vasomotion
Slow, intermittent flow through capillaries
Gasses and Nutrients diffuse ________________
Down Concentration Gradient
Bulk Flow
Fluid leaves capillaries are arterial end, returns to blood at venous end.
Direction and Amount of Fluid depend on:
Hydrostatic and Osmotic Pressure
Hydrostatic Pressure
Force of fluid against a barrier
Osmotic Pressure
Due to non-diffusible solutes, pulls fluid across a boundary
Net Filtration Pressure (NFP)
Comprises all forces acting on capillary bed
Equation to find NFP
NFP = (HPc+OPif)-(HPif+OPc)
HPc
Hydrostatic Pressure of Capillary, out flow
OPif
Osmotic Pressure of Interstitial fluid, out flow
HPif
Hydrostatic Pressure of Interstitial Fluid, influx
OPc
Osmotic Pressure of Capillary, influx
Lymphatic System
Returns fluid that leaks out of the blood vessels
Lymph
Fluid in vessels
Lymph Nodes
Cleanse Lymph
Function of Lymphoid Organs and Tissues
Protect body from pathogens, house phagocytic cells and lymphocytes
Lymph flows ________________
One way, towards the heart
Lymphatic Vessels from Largest to Smallest
Trunks and Ducts, Collecting Lymphatic Vessels, Lymphatic Capillaries
Lymphatic Capillaries
Blind end, absorb fluid, Endothelial cells overlap, Form one way mini valves, Pathogens travel through body
Lymphatic Vessels
Pathogens travel through body, return interstitial fluid and leaked plasma protein back into blood. Flows through increasingly larger channels.
Lymphatic Collecting Vessels
Similar to veins except thinner walls, more internal valves, Anastomose more frequently
Lymphatic Trunks
Formed by union of lymphatic collecting vessels. Deliver lymph into 2 ducts.
2 Big lymphatic ducts
Right Lymphatic and Thoracic Duct
Lymphatic Ducts
Empties lymph into venous circulation
Lymph Transport is propelled by:
Skeletal Muscle, Valves, Respiration Changes, Pulsation of arteries, Contraction of smooth muscle inside lymphatic walls.
T Cells (T Lymphocytes)
Manage immune response, attack and destroy infected cells
B Cells (B Lymphocytes)
Secrete Antibodies
Reticular Connective Tissue:
Houses and provides proliferation of lymphocytes, Surveillance point for lymphocytes and macrophages
Lymph Nodes
Clustered along lymphatic vessels, Filter lymph and activate immune system
2 functions of lymph nodes
Filter Lymph, Activate immune
Lymph Nodes have an external _______________
Fibrous Capsule
Cortex of a Lymph Node
Outside portion of the lymph node, contains follicles with germinal centers, Houses T cells
Medulla of a Lymph Node
Inside Portion of a Lymph Node
Germinal Centers
House B cells, inside the follicles of the cortex
Medullary Cords
Extend inward from cortex and contain T and B cells
Circulation through Lymph Nodes
Enters afferent vessels, fluid forced into interaction by germinal centers, flows into medulla and out efferent vessels
Function of the Spleen
Lymphocyte proliferation, immune surveillance and response, cleanses blood of aged cells and platelets, macrophages remove debris
White Pulp of Spleen
Lymphocytes
Red Pulp of Spleen
RBC’s and everything but lymphocytes
Function of Thymus
No follicles and No B cells, T lymphocyte maturation, doesn’t directly fight antigens,
Mucosa Associated Lymphoid Tissue (MALT)
Housed in mucous membranes throughout the body.
Function of MALT
Protects from pathogens.
Largest concentrations of MALT
Tonsils, Peyer’s Patches, Appendix
Tonsils
Form a ring around pharynx, gather and remove pathogens in food or air
Palatine Tonsils
Posterior of Oral Cavity
Lingual Tonsils
Base of Tongue
Pharyngeal Tonsils
Posterior of nasopharynx
Tonsil Structure
Follicles w/ Germinal Centers, Epithelium forms crypts and forces interaction of pathogens.
2 Clusters of Lymphoid Follicles
Peyer’s Patches and Appendix
Peyer’s Patches
Small Intestine
Appendix
Offshoot of large intestine
Function of Follicle Clusters
Destroy Bacteria, Generate memory lymphocytes