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190 Cards in this Set
- Front
- Back
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Types of Blood Vessels |
1. Arteries 2. Arterioles 3. Capillaries 4. Venules 5. Veins |
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Arteries |
Carry blood away from the heart |
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Arterioles |
Smallest branches of arteries |
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Capillaries |
*Smallest blood vessels *Only place where gas exchange can occur |
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Venules |
Collect blood from capillaries |
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Veins |
Return blood to the heart |
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Vessel Walls |
Three Layers: 1) TUNICA INTIMA (inner layer) -endothelial lining and connective tissue layer *only layer connected to blood itself 2) TUNICA MEDIA (outer layer) -concentric sheets of smooth muscle in loose connective tissue *significantly less in vein vs. in artery
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Vessel Walls Ctd |
3) TUNICA EXTERNA (outer layer) -anchors vessel to adjacent tissues in arteries -contains collagen fibers -elastic fibers -In veins -Vaso Vasorum** (vessels of vessels) -small arteries and veins -in walls of large arteries and veins -supply cells of tunica media and externs
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If vessel is too big and can't do gas exchange? |
Vaso Vasorum |
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Differences between arteries and veins |
1. arteries and veins run side by side 2. Arteries= thicker walls, higher pressure 3. Collapsed artery has small, round lumen 4. Vein has large flat lumen 5. Vein lining contracts, artery doesn't 6. artery lining folds 7. arteries more elastic 8. veins have valves |
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Structure & Function: Arteries |
*Elasticity allows arteries to absorb press waves that come with each heartbeat -Contractility (change in diameter) -Controlled by sympathetic division of ANS: 1. Vasocontriction--> contraction of arterial smooth muscle 2. Vasodilation--> relaxation of arterial smooth muscle, enlarging the lumen *Together these processes affect: -afterload on heart, peripheral BP, capillary blood flow |
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Structure & Function: Arteries Ctd |
*From heart to capillaries, arteries change from elastic arteries to muscular arteries to arterioles! 1. ELASTIC ARTERIES: aka conducting arteries -large vessels ex. aorta, pulmonary trunk -tunica media has lots elastic fibers, few muscle cells -elasticity evens out pull force 2. MUSCULAR ARTERIES aka distribution arteries -medium sized (most arteries) -tunica media= many muscle cells 3. ARTERIOLES -are small, have thin or incomplete tunica media and little to no tunica externe |
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Structure & Function of Capillaries |
*smallest vessels with thin walls -microscopic capillary networks permeate all active tissues -Function: 1. all exchange functions of cardiovascular system 2. materials diffuse btwn blood & interstitial Fluids |
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Capillary Structure Ctd. |
*endothelial tube inside basement membrane -no tunica media -no tunica externa -diameter similar to RBC |
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Three Types of Capillaries |
1. Continuous 2. Fenestrated 3. Sinusoids
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Continuous Capillaries |
1. Have complete endothelial lining 2. Found in all tissues except epithelia & cartilage 3. Permit diffusion of water, small solutes and lipid-soluble materials 4. Block blood cells and plasma proteins
Specialized Continuous: - in CNS and thymus -restricted permeability -ex. Blood Brain Barrier |
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Fenestrated Capillaries |
1. Have pores in endothelial lining 2. Permit rapid exchange of water and larger solutes btwn plasma and interstitial fluid 3. found in Chorid plexus, Endocrine organs, Kidneys, Intestinal Tract |
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Sinusoidal Capillaries |
1. Have gaps btwn adjacent endothelial cells 2. Found in Liver, Spleen, Bone Marrow, Endocrine Organs 3. Permit free exchange of: -water and large plasma proteins -btwn blood & interstitial fluid 4. Phagocytic cells monitor blood at sinusoids
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More Structure and Function of Capillaries |
1. Capillary Beds 2. Precapillary sphinctor 3. Thoroughfare channels 4. Collaterals
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Capillary Beds |
aka Capillary plexus *connect one arteriole and one vein |
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Precapillary Sphinctor |
1. Guards enterance to each capillary 2. Opens and closes, causing capillary blood to flow in pulses |
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Thoroughfare Channels |
1. Direct capillary connections btwn arterioles and venules 2. Controlled by smooth muscle segments (met arterioles) |
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Collaterals |
1. Multiple arteries that contribute to one capillary bed 2. Allow circulation if one artery is blocked
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Arterial Anastomosis |
Fusion of two collateral arteries |
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Arteriovenous Anastomosis |
Direct connections between arterioles and venules without the capillary bed |
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Veins (general) |
1. Collect from capillaries in tissues and organs and return to the heart 2. Larger in diameter than arteries 3. Thinner walls than arteries 4. Lower BP |
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Venules |
Very small veins which collect blood from capillaries |
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Medium Sized veins |
1. Thin tunica media and few smooth muscle cells 2. Tunica extern with longitudinal bundles of elastic fibers |
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Large Veins |
1. all three tunica layers, just like large arteries 2. Thick tunica externa and thin tunica media |
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Venous Valves |
1. Made out of folds of tunica intima 2. To prevent blood from flowing backward 3. Support from muscles and compression pushed blood back toward heart in unilateral direction |
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Venous System |
60-65% of blood
*is a very compliant system, collapsable and expandable |
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Most of the Blood in our body... |
Is in the venous system and capillary bed |
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Capacitance of a Blood Vessel |
The ability to stretch -relationship btwn blood volume and blood pressure -veins (capacitance vessels) stretch more than artereis
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Venous Response to blood loss |
1. Vasomotor centers stimulate sympathetic nerves 2. Systemic veins constrict 3. Veins in the liver, skin and lungs redistribute VENOUS RESERVE |
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Afterload |
Aka Peripheral Vascular Resistance (PVR) |
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Pressure and Resistance |
1. PRESSURE: heart generates pressure to overcome resistance (pressure gradient more important than absolute pressure) 2. PRESSURE GRADIENT: difference btwn pressure at the heart and at peripheral capillary beds 3. FLOW: proportional to pressure difference divided by R |
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Monitoring Pressure |
1. Blood Pressure -Arterial pressure 2. Capillary Hydrostatic Pressure (CHP) -pressure within the capillary beds 3. Venous Pressure -pressure in the venous system |
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Circulatory Pressure |
-Change in pressure across the systemic circuit -Circulatory pressure must overcome TOTAL PERIPHERAL RESISTANCE (resistance of entire cardiovascular system) |
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Total Peripheral Resistance Depends on |
1. Vascular Resistance 2. Viscosity 3. Turbulence |
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Blood Flow |
Volume of blood flowing per unit of time through a vessel or group of vessels
*equal to cardiac output |
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Blood Pressure |
Hydrostatic pressure in the arterial system that pushes blood through capillary beds |
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Circulatory Pressure |
Pressure difference between the base of the ascending aorta and the entrance to the right atrium |
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Hydrostatic Pressure |
Pressure exerted by a liquid in response to an applied force |
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Peripheral Resistance |
Resistance of the arterial system; affected by vascular resistance, viscosity and turbulence |
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Resistance |
A force that opposes movement |
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Total Peripheral Resistance |
Resistance of the entire cardiovascular system |
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Vascular Resistance |
Resistance due to friction within a blood vessel mostly btwn blood and vessel walls |
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Venous Pressure |
Hydrostatic pressure in the venous system |
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Viscosity |
Resistance to flow due to interactions among molecules within a liquid |
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Overview of Cardio Pressures |
1. Vessel Diametes 2. Total cross-sectional areas 3. Pressures 4. Velocity of blood flow |
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Vessel Diameter |
Biggest=vena cava, aorta Smallest= capillaries |
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Cross Sectional Areas |
Mostly in capillaries which is good bc this is where we do gas exchange |
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Average Blood Pressure |
Hightest in the aorta, elastic arteries
Lowest in the veins, vena cava
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Velocity of Blood Flow |
lowest in capillaries |
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Systolic Pressure |
Peak arterial pressure during ventricular systole |
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Diastolic Pressure |
*in diastolic longer than systolic -minimum arterial pressure during diastole |
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Pulse Pressure |
Difference btwn systolic and diastolic pressures |
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Mean arterial Pressure |
diastolic pressure + 1/3 pulse pressure |
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Hypertension |
Greater than 140/90 |
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Respiratory Pump |
Refers to thoracic cavity action! -inhaling decreases thoracic pressure -exhaling raises thoracic pressure |
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Diffusion |
Movement of ions/molevules from high to low concentration along the concentration gradient |
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Filtration |
Driven by hydrostatic pressure -water and small solutes forced through capillary wall leaving larger solutes behind in bloodstream |
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Reabsorption |
Driven by osmotic pressure -Blood colloid osmotic pressure -->pressure required to prevent osmosis |
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Capillary Exchange |
1. At arterial end= fluid moves out of capillary into interstitial fluid
2. At venous end= fluid moves into capillary and out of interstitial fluid
*transition between filtration and reabsorption is closer to venous end
*capillaries filter more than they absorb -excess fluid enters lymphatic vessels |
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Tissue Perfusion |
Blood flow through the tissue!! -carries O2 and nutrients to tissues/ organs -carries CO2 and wastes away
Affected by: 1. cardiac output 2. Peripheral resistance 3. Blood pressure |
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Cardiovascular Regulation |
Controlling Cardiac Output and Blood Pressure: 1. Autoregulation -causes immediate, localized homeostatic adjustments 2. Neural Mechanisms -respond quickly to changes at specific sites 3. Endocrine Mechanisms -direct long term changes
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Autoregulation |
Due to opening and closing of pre capillary sphincters due to local release of vasodilator or vasoconstrictor chemicals from the tissues |
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Central Regulation |
(Neuroendocrine) mechanisms that control the total systemic circulation. This regulation involves both the cardiovascular and vasomotor centers |
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More Cadiovascular Reg |
1. ADH -released by pituitary -increases BP by reducing water loss at kidneys (responds to low blood volume)
2. Angiotensin II -responds to fall in renal blood pressure -stimulates: ADH production, thirst, peripheral vasoconstriction and cardiac output
3. Erythropoietin (EPO) -released at kidneys -responds to low BP, low o2 content in blood -stimulates RBC production |
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Natriuretic Peptides in response to high BP |
1. Atrial Natriuretic (ANP) -produced by cells in Right Atrium 2. Brain Natriuretic (BNP) -produced by ventricular muscle cells
*respond to excessive diastolic stretching *lower blood volume and pressure *reduces stress on the heart |
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Cardiovascular Response to Exercise |
1. LIGHT EXERCISE -vasodilation in area of interest (legs), increases circulation -venous return increases w/ muscle contractions -cardiac output rises 2. HEAVY EXERCISE -activates sympathetic nervous system -cardiac output increases to maximum (about 4 times resting level) -restricted blood flow to nonessential organs -redirects blood flow to skeletal, lungs and heart -blood supply to brain=unaffected |
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Vena Cava |
enters belly at T8
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Oesophagus |
enters at T10 |
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Abdomen Aorta |
enters at T12 |
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L1 |
Celiac Trunk |
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L2 |
Superier Mesenteric Artery |
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L3 |
Inferior Mesenteric Artery |
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Anastomoses |
Where vessels come together |
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Pulmonary Circuit |
1. Pulmonary Arteries: -carry deoxygenated blood -Pulmonary trunk= branches to left and right pulmonary arteries -pulmonary arteries branch into pulmonary arterioles -pulmonary arterioles branch into capillary networks that surround alveoli |
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Pulmonary Vessels |
1. Pulmonary veins -carry oxygenated blood -capillary networks around alveoli join to form venules -venules join to form 4 pulmonary veins -veins empty into left atrium |
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Systemic Circuit |
1. Contains 84% of blood volumes 2. Supplies the entire body (except pulmonary circuit)
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Systemic Arteries |
1. Blood moves from left ventricle into ascending aorta 2. Coronary arteries- branch from aortic sinus |
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Branches of the Aortic Arch |
*deliver blood to head, neck, shoulders and upper limbs 1. Brachiocephalic Trunk 2. Left Common Carotid Artery 3. Left Subclavian Artery |
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Subclavian Arteries |
Leaving the thoracic cavity: -become axillae artery in arm -brachial artery distally |
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Brachial Artery |
*Divides at coronoid fossa of humerus into: 1. Radial artery 2. Ulnar artery Fuse at wrist to form: 1. Superficial and deep palmar arches 2. Which supply digital arteries
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Common Carotid Arteries |
Each Common Carotid Divides into: 1. External carotid -supplies blood to neck, lower jaw, face 2. Internal carotid -enters skull & delivers blood to the brain -divides into three branches: 1. Opthalmic artery 2. Anterior Cerebral artery 3. Middle Cerebral artery |
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Descending Aorta |
THORACIC AORTA: -supplies organs of the chest 1. bronchial arteries 2. Pericardial arteries 3. Esophageal arteries 4. Mediastinal arteries -supplies chest wall 1. intercostal arteries 2. superior phrenic arteriesS |
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Systemic Veins |
In neck and limbs: -one set of arteries (deep) -two sets of veins (one deep, one superficial)
*venous system controls body temperature |
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Superior Vena Cava |
Receives blood from tissues and organs of: 1. head 2. neck 3. chest 4. shoulders 5. upper limbs |
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Veins of the Hand |
Superficial arch empties into: 1. cephalic vein 2. median antebrachial vein 3. basilic vein 4. median cubital vein
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Brachiocephalic Vein |
Receives Blood From: 1. vertebral vein 2. internal thoracic vein
* L & R brachiocephalic veins merge to form Superior Vena Cava |
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Tributaries of Superior Vena Cava |
1. Azygos vein & Hemiazygos vein which receive blood from: -intercostal veins -esophageal veins |
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Inferior Vena Cava |
Collects Blood from organs inferior to the diaphragm |
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Major Tributaries of Abdominal Inferior Vena Cava |
1. lumbar veins 2. gonadal veins 3. hepatic veins 4. renal veins 5. adrenal veins 6. phrenic veins |
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Hepatic Portal System |
1. Connects two capillary beds 2. Delivers nutrient laden blood -from capillaries of digestive organs -to liver sinusoids for processing |
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Tributaries of the Hepatic Portal Vein |
1. Inferior Mesenteric Vein -drains part of LI 2. Splenic Vein -drains spleen, part of stomach & pancreas 3. Superior Mesenteric Vein -drains part of stomach, SI & part of LI 4. L & R Gastric Veins -drain part of stomach 5. Cystic Vein -drains gallbladder |
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FIVE AGE RELATED CHANGES IN THE HEART |
1. reduced maximum cardiac output 2. changes in nodal and conducting cells 3. reduced elasticity of cadiac skeleton 4. progressive atherosclerosis 5. replacement of damaged cardiac muscle cells by scar tissue |
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THREE AGE RELATED CHANGES IN BLOOD VESSELS |
1. arteries become less elastic -pressure change can cause aneurysm 2. Calcium deposits on vessel walls -can cause stroke or infarction 3. Thrombi can form -at atherosclerotic plaques
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Pressure For Venous System |
Created by the muscle bed itself--> create pressure around the vessels and make sure blood can flow back to the heart |
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Colloid |
Particles |
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Important Functions of Blood |
1. Transport dissolved substances 2. Regulate pH and ions 3. Restriction of fluid losses at injury sites 4. Defense against toxins and pathogens 5. Stabilization of body temp |
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Whole Blood |
1. Plasma -fluid consisting of water, plasma proteins and other solutes 2. Formed elements -all cells and solids |
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Types of Formed Elements |
1. RBCs or Erythrocytes -transport oxygen 2. WBCs or Leukocytes -part of immune system 3. Platelets -cell fragments involved in clotting |
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General Characteristics of Blood |
1. 38 C normal temp 2. High viscosity 3. Slightly alkaline 7.35-7.45 pH
*blood volume= 7% of body weight |
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Composition of Plasma |
1. Makes up 50-60% of blood volume 2. More than 90% of plasma is water 3. Extracellular Fluids -IF and plasma -plasma and IF exchange across capillary walls -water -ions -small solutes
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Plasma Proteins |
1. Albumins (60%) 2. Globulins (35%) 3. Fibrinogen (4%)
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Albumin |
Transport substances such as fatty acids, thyroid hormones and steroid hormones |
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Globulins |
-antibodies, also called immunoglobulins -transport globulins (small molecules |
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Fibrinogen |
Molecules that form clots and produce long, insoluble strands of fibrin |
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Serum |
1. Plasma= part of blood that contains both serum & clotting factors 2. Serum= part of blood that remains once clotting factors like fibrin have been removed 3. Plasma contains clotting factors & water, serum contains proteins like albumin & globulins |
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Origins of Plasma Proteins |
1. More than 90% made in liver 2. Antibodies made by plasma cells 3. Peptide hormones made by endocrine organs
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Abundance of RBCs |
Red Blood Cell Count= # of RBCs in 1 microliter of whole blood
Hematocrit=packed cell volume, % of RBCs in centrifuged whole blood |
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Red Blood Cells |
*small, highly specialized discs *thin in middle & thicker at edge
NO NUCLEUS |
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Important Effects of RBC Shape on Function |
1. high surface-to-volume ratio -quickly absorbs and releases oxygen 2. discs form stacks called rouleaux -smooth flow through narrow vessels 3. bend and flex entering small capillaries |
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Life Span of RBCs |
*Lack nuclei, mitochondria & ribosomes -Means no repair and anaerobic metabolism
LIVE 120 DAYS!
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RBCs traveling through capilaries |
Stack like dinner plates |
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Hemoglobin |
1. Protein molecule that transports respiratory gasses 2. Normal hemoglobin 12-18 d/dL
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Hemoglobin Structure |
1. Complex quaternary structure 2. Four globular protein subunits -each with one molecule of heme -each heme contains 1 iron ion
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Iron Ions |
1. Associate easily with oxygen 2. Dissociate easily from oxygen 3. But has higher affinity for CO |
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Recycling RBCs |
*1% wear out per day (3 million per second) 1. Macrophages of liver, spleen & bone marrow engulf the damaged and worn out 2. Phagocytes break down hemoglobin into components -Heme to bilverdin -globular proteins to amino acids -iron
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Recycling RBCs ctd... |
3. Biliverdin converted to bilirubin 4. Bilirubin excreted by the liver (bile) 5. Iron removed from heme leaving biliverdin -to transport proteins -to storage proteins |
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Hemoglobinuria |
Hemoglobin breakdown products in urine due to excess hemolysis in blood stream |
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Hematuria |
Whole red blood cells in urine due to kidney or tissue damage |
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RBC Production |
1. Erythropoiesis -occurs only in myeloid tissue (red bone marrow) in adults 2. Hemocytoblasts -stem cells in myeloid tissue divide to produce: 1. Myeloid stem cells become RBCs, some WBCs 2. Lymphoid stem cells become lymphocytes |
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Building RBCs Requires... |
1. Amino acids 2. Iron 3. Vitamins B12, B6 4. Folic Acid |
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Erythropoietin (EPO) |
Hormone secreted from kidneys in response to low oxygen blood content of high elevation |
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Anemia! |
Can be caused by depressed... 1.Hematocrit 2. Hemoglobin Concentration 3. RBC count |
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Blood Types |
1. Type A 2. Type B 3. Type AB 4. Type O |
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Type A Blood |
1. Surface antigen is A 2. Type B antibodies
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Type B Blood |
1. Surface Antigen is B 2. Type A antibodies
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Type AB Blood |
1. Surface Antigens both A and B 2. Neither A nor B antibodies |
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Type O Blood |
1. No Surface Antigen 2. Both A and B antibodies |
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RH Factor |
(Also Called D Antigen)
1. Either Rh positive or Rh negative -only sensitized Rh blood has anti-Rh antibodies
1. Problems don't really happen during a 1st pregnancy bc very few fetal cells enter the maternal circulation and thus the moms immune system isn't stimulated to produce anti Rh antibodies
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Rh Factor Ctd... |
2. Most common form of hemolytic disease of the newborn occurs after an Rh- woman carried an Rh + fetus 3. Exposure to fetal RBC antigens generally occurs during delivery, when bleeding takes place at the placenta and uterus 4. Mixing of the blood can stimulate mother's immune system to produce anti Rh antibodies, leading to sensitization
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Rh Factor Ctd 3... |
5. B/C anti Rh antibodies aren't produced in large amounts until after a delivery, a woman's first infant isn't affected 6. In subsequent pregnancy, the mother is sensitized to the Rh + fetus and the anti Rh antibodies cross the placenta and attack the fetal RBCs |
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WBCs |
*No hemoglobin, have nuclei
Functions: 1. Defend against pathogens 2. Remove toxins & waste 3. Attack abnormal cells
Residence: 1. Most are found in connective tissue & lymphatic system
Characteristics: 1. Can migrate out of bloodstream 2. Attracted to chemical stimuli (positive chemotaxis)
*Some are phagocytic: 1. Neutrophils 2. Eosinophils 3. Monocytes |
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Neutrophils |
*AKA polymorphonuclear leukocytes
1. 50-70% of circulating WBCs 2. FIRST ON SITE TO KILL BACTERIA 3. Engulf & digest pathogens
Degranulation- remove granules from cytoplasm
Defensins- attack pathogen membranes
*release prostaglandins & leukotrines *form PUS |
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Eosinophils |
(Aciophils) 1. 2-4% of circulating WBCs 2. Attack large parasites 3. Excrete toxic compounds -nitric oxide -cytotoxic enzymes 4. SENSITIVE TO ALLERGENS, asthma? 5. control inflammation w/ enzymes that counteract inflammatory effects of neutrophils and mast cells
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Basophils |
*accumulate in damaged tissue and RELEASE HISTAMINE (to dilate vessels) and HEPARIN (to prevent clotting)
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Monocytes |
*biggest cells available in the body
1. Large, spherical 2. Become specialized and become macrophages 3. Secrete substances to attract immune system cells & fibrocytes to injured area |
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Lymphocytes |
(Specialized killers)**
1. T Cells -cell-mediated immunity -attack foreign cells directly
2. B Cells -Humoral immunity -differentiate into plasma cells -synthesize antibodies
3. Natural Killer (NK) cells -detect & destroy abnormal tissue cells (cancers) |
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WBC Production |
1. All blood cells originate from hemocytoblasts -which produce progenitor cells called myeloid stem cells & lymphoid stem cells
Myeloid Stem Cells: -produce all WBCs except lymphocytes
Lymphoid Stem Cells -Lymphopoiesis= production of lymphocytes |
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WBC Development |
1. WBCs except monocytes, develop in bone marrow 2. Monocytes= develop in macrophages in peripheral tissue |
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Regulation of WBC Production |
Colony Stimulating Factors (CSFs) -hormones that regulate blood cell populations |
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Platelets |
1. Cell fragments involved in clotting 2. Circulate for 9-12 days 3. Removed by the spleen 4. 2/3 are reserved for emergencies
Platelet Counts: 150-500 K
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Thrombocytopenia |
Abnormally low platelet count |
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Thrombocytosis |
Abnormally high platelet count |
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Functions of Platelets |
1. Release important clotting chemicals 2. Temporarily patch damaged vessel walls 3. Reduce size of a break in vessel wall |
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Platelet Prodcution |
AKA Thrombcytopoiesis!!
*occurs in bone marrow |
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Megakaryocytes |
1. Giant cells in bone marrow 2. Manufacture platelets from cytoplasm
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Hormonal Controls |
1. Thrombopoietin (TPO) 2. Interleukin-6 3. Multi-CSF |
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Hemostasis |
*Cessation of Bleeding!!
Three Phases: 1. Vascular phase 2. Platelet phase 3. Coagulation phase |
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Vascular Phase |
*cut triggers vascular spasm that lasts 30 mins*
1. Endothelial cells contract & expose basement membrane to bloodstream 2. Endothelial cells release local hormones, endothelins2. Endothelial cells release local hormones, endothelins 3. Endothelial plasma membranes become "sticky"; seal off blood flow |
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Platelet Phase |
1. Begins within 15 seconds after injury! 2. Platelet Adhesion -to sticky endothelial surfaces -to basement membranes -to exposed collagen fibers 3. Platelet Aggregation -forms platelet plug which closes small breaks! 4. Activated platelets release clotting compounds!
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Factors that Limit the Growth of the Platelet Plug |
1. Prostacyclin inhibits platelet aggregation 2. Inhibitory compounds released by other WBCs 3. Circulating enzymes break down ADP 4. Negative feedback from serotonin 5. Development of blood clot isolates area |
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Coagulation Phase |
1. Begins 30 seconds or more after the injury 2. Blood clotting (coagulation)
Clotting Factors: -also called procoagulants -proteins or ions in plasma -required for normal clotting |
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Coagulation Pathways |
1. Extrinsic 2. Intrinsic 3. Common |
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Feedback Control of Blood Clotting |
1. Anticoagulants (plasma proteins) -antithrombin III 2. Heparin 3. Aspirin 4. Protein C (activated by thrombomodulin) 5. Prostacyclin
*CALCIUM IONS and VITAMIN K are ESSENTIAL TO THE CLOTTING PROCESS
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Clot Retraction |
1. Pulls torn edges of vessels together -reduces residual bleeding & stabilizing injury site 2. Reduces size of damaged area -makes it easier for fibrocytes, smooth muscle cells & endothelial cells to complete repairs |
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Location of the Heart |
Mediastinum
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Pericardium |
*double lining of the pericardial cavity*
Visceral Pericardium -inner layer of pericardium
Parietal Pericardium -outer layer |
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Right Atrium |
Collects blood from systemic circuit |
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Right Ventricle |
Pumps blood to pulmonary circuit |
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Left Atrium |
Collects blood from pulmonary circuit |
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Left Ventricle |
Pumps blood to systemic circuit |
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Coronary Sulcus |
Divides atria and ventricles |
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Cardiac Muscle Cells |
1. Small 2. Single, central nucleus 3. Branching interconnections btwn cells 4. Intercalated discs |
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AV valves |
1. connect RA to RV and LA to LV 2. permit blood flow in one direction |
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Interatrial Septum |
separates atria
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Interventricular Septum |
separates ventricles |
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Coronary Sinus |
1. Cardiac veins return blood to coronary sinus 2. Opens into RA |
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Foramen Ovale |
1. Before birth is an opening through interatrial septum 2. Seals off at birth forming fossa ovals |
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Right AV Valve |
AKA tricuspid Valve
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Left AV Valve |
AKA bicuspid or mitral |
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Left Ventricle |
1. Holds same volume as right ventricle 2. larger, muscle is thicker and more powerful 3. No moderator band |
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Differences btwn L and R Ventricles |
1. R ventricle wall is thinner, less pressure than left ventricle 2. R ventricle is pouch shaped, left is round |
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Aortic Sinuses |
1. At Base of Ascending aorta 2. Sacs that prevent valve cusps from sticking to aorta |
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Two Types of Cardiac Muscle CElls |
1. Conducting System -controls and coordinates heartbeat 2. Contractile Cells -produce contractions that propel blood |
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Conducting System |
1. SA node-wall of R atrium 2. AV node 3. Conducting Cells
SA node depolarizes 1st, establishing Heart Rate!
*SA node contains pacemaker cells! |
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Conducting System Ctd... |
1. SA node and atrial activation begin 2.Stimulus spreads across atrial surfaces and reaches AV node 3. 100-msec delay at AV node. Atrial contraction begins 4. impulse travels along inter ventricular septum to Purkinje fibers & papillary muscles of RV 5. Impulse distributed by Purkinje Fibers. Atrial Contraction is complete, ventricular contraction begins!
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ECG |
Recording of electrical events in the heart!
1. P wave 2. QRS complex 3. T wave 4. P-R interval 5. Q-T interval |
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P Wave |
Atria Depolarize! |
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QRS Complex |
Ventricles Depolarize!
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T Wave |
Ventricles Repolarize |
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P-R Interval |
From start of atrial depolarization to start of QRS complex
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Q-T Interval |
From ventricular depolarization to ventricular repolarization |
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Cardiac Cycle |
Period between start of one heartbeat and beginning of the next! -includes both contraction & relaxation!
Two Phase: 1. Systole (contraction) 2. Diastole (relaxation) |
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Heart Sounds |
S1= produced by AV valves S2= semilunar valves
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Heart Murmer |
Regurgitation through valves! |
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Cardiac Output |
Volume pumped by Left Ventricle in 1 min!
CO=HR X SV |
