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What does the Cardiovascular System transport throughout the body? - Answer From the external environment: nutrients, water, and gases. Between cells: Hormones, antibodies, and immune cells Waste Eliminated: Metabolic waste, heat, CO What is the difference between pulmonary arteries and pulminary veins? - Answer Pulminary arteries carry DEOXYGENATED BLOOD TO the lungs pulmonary veins carry oxygenated blood back to the heart. What are the principles of pressure gradient and blood flow? - Answer Blood always flows from high to low pressure Pressure is lost due to resistance in the vessels Flow is proportional to pressure to pressure gradient Pressure is only affected by the DIFFERENCE of pressures Describe Poiseuille's Law - Answer - F = ΔP πr^4 / 8ηL
- η is blood viscosity
- L is length of vessel In layman's terms, radius has the greatest affect on blood flow. Resistance is less with a greater radius. Note that velocity is not the same as flow Describe Mean Arterial Pressure - Answer Primary Driving Force for Blood Force Pressure that is reserved in the arteries after heart relaxation Describe the heart, blood flow, and the structures blood passes through. - Answer 4 chambers myocardium that is cased in pericardium Deoxygenated: Vena Cava, right atrium, tricuspid valve, right ventricle, semilunar valve, Pulmonary artery.
Oxygenated: Pulminary Vein, Left Atrium, bicuspid valce, Left Ventricle, Aorta Forms from a tube in development Chordae Tendonae prevent eversion these attach to papillary muscles What is the difference between the Tricuspid Valve and Bicuspid Valve (Mitral). - Answer Tricuspid is between the R atrium and R Ventricle Biscuspid (Mitral) is between the L atrium and L Ventricle Semilunar is division of R ventricle and Pulm. artery These prevent backflow in the heart Briefly describe coronary circulation of the heart. - Answer This supplies the heart with blood. Left coronary and Right Coronary Heart attacks associated with coronary bypass. What are the main difference between autorhythmic and contractile cells? - Answer Autorhythmic: Signal Contraction Do not have organized sarcomeres Fewer Contractile Fibers Contractile cells: Striated fibers organized into sarcomeres single nucleus connected by intercalated discs gap junctions SR is smaller mitochondria acts as 1/3 volume Describe the events leading up to a contraction in a cardiac contractile fiber. - Answer Action potential enters from adjacent cell Voltage gated Ca2+ opens Ca2+ is released from RyR receptors Local release sparks Ca2+ release
P Wave - Depolarization of atria QRS Complex - Depolarization of the Ventricles and Repolarization of the atria T Wave - Repolarization of the ventricles PR - AV delay TP - ventricular and atrial relaxation What is heart rate defined as in reference to an ECG? - Answer Distance between two Q waves. What is the difference between bradycardia and tachycardia? - Answer Brady - slow heart rate Tachy - fast (D fib, arrhythmia) What is systole and diastole? - Answer systole (contraction) and diastole (relaxation) Describe the 5 phases of heart contraction. - Answer Phase 1: Atrial and Ventricular Diastole Atria are filling up AV valves open and fill ventricles Phase 2: Atria contract and eject last 20% of blood into the ventricles. End Diastolic Volume (EDV) happens at the end of ventricular relaxation Phase 3: "Lub" and Early contraction No blood in or out due to isovolumetric contraction builds ventricular pressure Atria relax to let blood flow in Phase 4: Semilunar Valves open and blood is ejected out of the ventricles End systolic volume is the volume at the end of ventricular ejection (ESV) Phase 5 "Dub" Ventricular relaxation semilunar valves shut also isovolumetric What are the equations associated with cardiac output - Answer SV*HR=Cardiac Output
SV = EDV-ESV
Describe sympathetic and parasympathetic control of the heart. - Answer parasympathetic slows heart (muscarinic with AcH) Ca2+ permeability decreases. less contraction K+ permeability increases sympathetic speeds up heart and increases contractility (sympathetic B1 receptors) increases pacemaker depolarization Tonic control is dominated by parasympathetics
Controlled in medulla oblongota
What influences stroke volume in the heart - Answer Blood volume at the beginning of the contraction Degree of stretch is preload
Frank Starling Load is proportional to EDV
EDV is determined by venous return which is affected by:
skeletal muscle pump respiratory pump sympathetic innervation of veins (dilation)
What is the contractility of the heart and what agents affect it? - Answer Controlled by inotropic agents
Positive inotropic increases contractility such as EP norEP and digitalis
Continuous and Fenestrated
Describe the general anatomy of veins in the body. - Answer Venules are what capillaries drain into.
They have convergent flow and small epithelium exchange site.
Veins are volume reservoir and much less elastic than arteries.
Have one way valves that prevent backflow
What is angiogenesis and why is it important? - Answer Creation of new blood vessels
Aids skeletal and heart blood flow
Wound and uterine line healing
controlled by angiogenic and antiangiogenic cytokines (Promoted by Vascular endothelial growth factor (VEGF) and Fibroblast Growth Factor (FGF). inhibited by angiostatin and endo statin
Regulating this could prevent malignant tumors Also could prevent heart disease
Describe what Mean Arterial Pressure - Answer Diastolic + 1/3(systolic - diastolic) 70 is hypo 100 is hyper
Pressure deteriorates when you hit the capillaries.
What are all the factors that can influence mean arteriole pressure? - Answer Blood volume (Fluid intake and loss regulated by kidneys)
Effectiveness as heart as a pump
Resistance is Diameter of arteries
Distribution between arteriole and venous blood flow is diameter of veins.
Resistance to one smaller vessel does NOT impact total flow (see image with 4 vessels
Describe the resistance mechanism in the arterioles. - Answer Local, Sympathetic, and hormones
Myogenic autoregulation vascular muscle regulates itself Ca2+ channels contract to prevent stretching
Paracrine signals influence vascular smooth muscle Active metabolic and Passive (occlusive) hyperemia. kinins histamine and NO3 all dialators
Describe regulation of the cardiovascular system - Answer Baroreceptors in carotid and aorta produce tonic action potentials
genetics
Can control: smoking, obesity, sedentary lifestyle, untreated hypertension
How does atherosclerosis develop? - Answer LDL build up from poor diet connects to endothelial tissue and oxidizes platelets become exposed to plaque and form a blood clot.
What are treatment options for high BP? - Answer calcium channel blocker ace inhibitor diuretics beta blocking drugs angiotensin receptor block
What are the cellular elements of blood? - Answer RBCs - Erythrocytes - transport oxygen and CO2 - live 120 days (longest) and stay skinny for transport Plateles - Megakaryocytes WBCs Lymphocytes - immune - Monocytes - macrophage Neutrophils - phagocytes - ingest foreign substances Eosinophils - granulocyes - invade toxins Basophils - mast cells?
Platelets - essential for clotting
How are blood cells made? - Answer In Bone Marrow
Hematopoiesis controlled by cytokines
Hematopoietic stem cells
Erythroblast - Reticulocyte - Erythrocyte Megakaryocytes form Platelets
What regulates each kind of blood cell? - Answer Colony stimulating Factor - Leukopoiesis (WBCs) endothelium for all cells
Thrombopoietin - Platelets (Liver) - megakaryocytes
Erythropoietin - RBCs (kidneys) (RBCs have no nucleus)
Describe Hemoglobin synthesis - Answer NEEDS iron 4 heme groups 4 globin groups
Iron comes from diet and taken up in bone marrow stored as ferritin
Describe the death of a RBC as well as complications with RBCs. - Answer Rupture and Phagocytized in spleen amino acids are utilized for new proteins some iron is used in new heme groups
Extrinsic Pathway starts 3 (injury pathway) Common Pathways starts at 10 (thrombin converts fibrinogen into insoluble fibrin polymers and becomes part of the clot.
Fibrin - plasmin - activates plasminogen this gets you fibrin fragments
describe the mechanisms of anticoagulation - Answer two mechanisms that limit the extent of clotting inhibition of platelet adhesion inhibition of coagulation cascade and fibrin formation hemophilia - cascade is defective somewhere
What are the functions of respiratory system? - Answer Exchange of gases between the blood and atmosphere Homeostatic regulation of pH Protection from irritating substances and pathogens Vocalization
Explain flow in the respiratory system - Answer Bulk Flow From higher pressure to lower pressure A muscular pump creates a pressure gradient Resistance is heavily influenced by diameter
What is the difference between ventilation and respiration? - Answer Ventilation - exchange of air between lungs and atmosphere
Respiration - movement of gases between the environment and the body's cells
What does the upper tract of the respiratory system consist of? - Answer Mouth, nasal cavity, larynx, pharynx
What does the lower tract of the respiratory system consist of? - Answer Trachea, two primary bronchi, their branches, and lungs
Alveoli (THIS IS WHERE GAS EXCHANGE HAPPENS)
What are the parts of the thoracic cage? - Answer Bones and ribs surrounding thorax Diaphragm, intercostals, SCLs, scalenes pleural sacs surrounding each lung
Pleura, parietal and visceral alleviates friction against thoracic wall
Describe the pathway of air from the mouth to the lungs. - Answer Pharynx - Larynx (vocal chords) - Trachea - Primary Bronchi - Secondary Bronchi
What does this airway do as air travels to the lungs? - Answer Warms to body temperature, humidifies, and filters out foreign irritants.
If this doesn't happen, dehydration can occur
Describe type I and type II alveolar cells. - Answer Type I - gas exchange Type II - surfactant secretion
Describe the path of pulmonary circulation. - Answer Right Ventricle - Pulmonary Trunk -
Passive vs Active
What is compliance vs elastance? - Answer Compliance - ability to stretch Low Compliance associates with restrictive lung disease. (Fibrosis and Low surfactant NRDS)
Elastance is ability to return back to normal volume after force is released (Emphysema)
Describe LaPlace's law and surfactant. - Answer P=2T/r Pressure, Surface Tension, and radius
Surfactant - Disrupt cohesiveness of water proteins and phospholipids More concentrated in smaller alveoli
Newborns sometimes have insufficient surfactant (NRDS)
MORE SURFACTANT DECREASES SURFACE AREA (this aids respiration)
Big area is easier to ventilate, smaller areas are harder to ventilate
Describe the sympathetic and parasympathetic response in the respiratory system. - Answer parasympathetic - airway constricts
sympathetic - dilates in response to epinephrine (B2 receptors)
What is total pulmonary ventilation and alveolar ventilation - Answer Ventilation Rate*TV
TV - Dead Space (alveolar)
What are the different types of ventilation? - Answer Eupnea - Normal
Hyperpnea - Increased rate due to metabolism (exercise)
Hyperventilation - Increased rate w/o metabolism (blowing up a balloon)
Hypoventilation - Decreased alveolar ventilation (asthma)
Tachypnea - panting - rapid panting
Dyspnea - difficulty - various pathologies and hard exercise
Apnea - cease of breathing (holding breathing) CNS depression
Normal Ventilation values - Answer Total pulmonary ventilation - 6L/min Total alveolar ventilation - 4.2L/min Maximum voluntary volume - 125-160L/min Respiration Rate - 12-20 breaths a minute
Fresh air into lungs is 10% of lung volume after inspiration
Alveolar flow and ventilation are matched for efficient exchange
What are the obstructive lung diseases? - Answer COPD chronic bronchitis
Venous Po2 - 40 PCo2 - 46 pH - 7.
Describe exchange between o2 and co2 in body (partial pressure) - Answer o2 is higher in atmosphere co2 is higher in blood
high to low
tissue
o2 is higher in blood co2 is higher in tissue
What affects alveolar gas exchange? - Answer Depth of Breathing Airway Resistance Lung Compliance surface area Diffusion distance CONCENTRATION GRADIENT
Pathologies that affect hypoxia. - Answer Emphysema - less surface area Fibrotic Lung Disease - Increased membrane Pulmonary Edema - Increased Distance Asthma - Bronchoconstriction - Low Po
How does gas solubility affect diffusion? - Answer pressure gradient of gas solubility of gas in liquid temperature
Describe the relationship of hemoglobin and oxygen. - Answer oxygen binds to hemoglobin at 4 heme sites. '2nd to hemoglobin, hemoglobin transports oxygen
Po2 determines amount of oxygen that become bound
What are the factors that affect O2 Hemoglobin binding affinity? - Answer Plasma pH, Temperature, pCo
Describe the o2 saturation curve - Answer shift right is decreased affinity and higher o ph is up and temp and pco2 is down
shift left is increased affinity with lower o ph is down and temp and co2 are up
2,3 BPC is chronic hypoxia and shifts curve RIGHT which is decreased affinity
Plasma o2 and amount of hemoglobin
What are the 3 ways the carbon dioxide is transported? - Answer Dissolved in plasma Bound to RBC or the most common - converted to BICARBONATE Bicarb enters plasma in exchange for Cl-
