Cardiovascular system study guide
What are the three functions of the circulatory system
1)transport 2) regulation 3) protection
What is the amount of blood contained in the body, what is the function of the blood?
5-6L of blood, and the function is to transport oxygen and nutrients all over the body as well as remove wastes (CO2)
blood typing classification system
ABO system
List the different classes of plasma proteins and describe their functions
Albumin: 60-80% of plasma protein; functions to help maintain blood osmotic pressure and give viscosity to the blood; therefore, maintaining blood volume and blood pressure Globulins: 36% of plasma protein Alpha: transport lipids and fat soluble vitamins Beta: transport lipids and fat soluble vitamins Gamma: constitute anti-bodies of immunity Fibrinogen: 4% of total plasma protein; assist thrombocytes in the formation of blood clots
What is the difference between arterial and venous blood?
Arterial: oxygenated; oxyhemoglobin Found in arteries and pulmonary vein Oxygen-hemoglobin saturation 97-98% Bright red in color Venous: deoxygenated; deoxyhemoglobin Found in veins and pulmonary artery Oxygen-hemoglobin saturation 75% Darker in color (blue)
arteries carry blood away from the heart (arterioles do as well but are smaller), capillaries are exchange vesicles, veins carry blood away from the heart (venules do as well but are smaller)
Arteries, arterioles, capillaries, venules, veins
: specialized mass of conducting cells located at eth atrioventricular junction of the heart
Atrioventricular node (AV node)
Why is the capillary conserved to be the "functional unit" of the circulatory system
Because this is where the necessary exchange for the body takes place
. Understand the changes in the redistribution of blood flow from rest to exercise. Is blood flow redistributed during exercise?
Blood is distributed to the regions of the body depending on the need for blood flow in the region. Resting conditions have different needs than exercise does. When we exercise, blood flow is directed to where it is needed, our muscles. When at rest it may be used more for digestion or other processes. The body accommodates for its own needs.
systole= period when either the ventricles or the atria are contracting ; diastole= period of the cardiac cycle when either the ventricles or the atria are relaxing
Cardiac cycle (systole and diastole)
What is a reasonable value for resting cardiac output, heart rate, and stroke volume?
Cardiac output: 5.6 L/min Heart Rate: 80 bts/min Stroke volume: 0.070 L/beat
What is meant by cardiac output and what is its significance?
Cardiac output: the volume of blood pumped by one ventricle per minute; it is significant because insufficient cardiac output or over active output causes problems, also it adjusts to the needs of the cells in the body
: pulmonary is to the lungs, coronary is back to the heart, and systemic is all over the body
Circulatory Routes (pulmonary, coronary, systemic)
What is the function of the precapillary sphincter
Cuff of smooth muscle fibers that surround the root of each true capillary at the metaarteriole that act as a valve to regulate blood flow into the capillary
What is represented by systolic and diastolic blood pressure? What is hypertension?
Diastolic pressure: arterial blood pressure reached during or as a result of diastole; lowest level of any given cardiac cycle Systolic pressure: pressure exerted by blood on the blood vessel walls during ventricular contractions Hypertension: high blood pressure
controls the activity of the heart = SA node, intranodal and intraatrial fibers, AV node, Bundle of His, R and L Bundle Branches, Purkinje Fibers
Electrical Activity
P wave; QRS complex; T wave: shows the electrical activity of the heart; P wave is atrial depolarization, T wave is ventricular repolarization, and the QRS is ventricular depolarization and atrial repolarization
Electrocardiogram (EKG)-
What is the purpose of the heart valves?
Ensures a smooth one way flow of blood through the heart
Indentify the different tissue layers that comprise the heart wall. How does the myocardium differ between the R and L atria and the R and L ventricles?
Epicardium: outer most layer Myocardium: thick middle layer that is composed of muscle cell that upon contraction "squeeze" or "wring" the heart Endocardium: inner most layer The mycocardium is relatively the same in the R and L atria, however, it is thicker in the L ventricle compared to the R ventricle
What are the differences between erythrocytes and leukocytes. Where is each produced and what is their function.
Erythrocytes: a. Red blood cells b. Most numerous type of blood cell c. No nucleus d. No mitochondria e. Contains hemoglobin which functions to transport oxygen and carbon dioxide within the blood f. Formed through erythropoiesis in myeloid tissue Leukocytes: a. White blood cells b. Function to aid in defense against infections by micro-organisms c. Contain a nucleus d. Contain mitochondria e. Can move in and out of the blood vessels (diapedesis) f. Many types g. Formed through leukopoiesis in myeloid and lymphoid tissues
main organ of the circulatory system; atria receive blood and ventricles pump it
Heart (right and left atria and ventricles
What are the average values for hemoglobin and hematocrit?
Hemoglobin: oxygen carrying protein of erythrocytes male = 13-18 g/100ml ; female = 12-16g/100ml Hematocrit: the % of total blood volume occupied by erythrocytes males = 47% ; females = 42%
blood cell formation; also called hematopoiesis
Hemopoiesis
Differentiate hemopoiesis, erythropoiesis, and leukopoiesis
Hemopoiesis: formation of blood cells Erythropoiesis: formation of RBC Leukopoiesis: formation of WBC
stoppage of bleed
Hemostasis
moment when both valves are closed after the contraction of the ventricles
Isolvolumetric relaxation:
split second in which the ventricles are completely closed chambers and blood volume in the chambers remains constant
Isovolumetric contraction phase
How does walking or jogging after exercise aid circulation recovery?
It aids in circulation recovery because it allows for a gradual slowing of your circulation for less strain on your heart and body, also, it will allow for sufficient time (and muscle contraction) to ensure the return of venous blood to the heart.
Where is the heart located?
It is protected by the thorax and lies in the thoracic cavity. Approximately 2/3 of its mass lies to the left of the mid-line of the sternum.
How is blood carried to and from the myocardium?
L and R coronary arteries and veins
What is the myocardium? How is it distinct from the other musculature?
Myocardium is the middle layer of the heart wall. It is distinct because it squeezes and wrings the heart to continue blood flow
Indentify the various component of waves of the EKG. Which are associated with atrial depolarization? Ventricular depolarization? Atrial repolarization? Ventricular repolarization?
P wave: Atrial Depolarization QRS complex: Ventricular depolarization and atrial repolarization T wave: Ventricular repolarization
Indentify the various phases of the cardiac cycle and state whether the phase is part of ventricular systole or diastole
Phase 1 (P wave) : ventricular diastole Phase 2 (QRS Complex) : ventricular systole Phase 3 (T wave) : ventricular diastole
: cuff of smooth muscle fibers that surround the root of each true capillary at the metarteriole
Precapillary sphincters:
How is venous pressure and venous blood flow maintained? Is this especially important during exercise?
Pressure and flow are maintained by the muscular and throaxic pumps. This is important so that sufficient blood flows back to the heart to continue the oxygen exchange cycle.
Pressure changes during cardiac cycle
Pressure increases as systole takes place (remember the stupid analogy with the water bottle and cap)
Identify the circulatory routes for blood flow throughout the body.
Pulmonary: to the lungs Coronary: to the heart Systemic: throughout the rest of the body
Understand the purpose of the venous valves and the skeletal muscle pump. What is the importance of this pump during exercise?
Purpose of the venous valves is to ensure one way directional flow of the blood to the heart (remember gravity will pull blood down in the lower extremities) The skeletal muscle pump moves blood along back to the heart from the veins. There is little smooth muscles in veins, and the contraction of muscles applies pressure to the veins forcing the blood through. The importance of this in exercise is to ensure that blood moves at a fast enough pace to keep enough blood going back to the heart
ventricles contract in atrial relaxation
QRS complex phases
increased pressure pushes the SL valve open allowing a surge of blood to leave the ventricles
Rapid ejection phase
when the ventricles are still contracting allowing the last bit of blood to enter the arteries
Reduced ejection phase
Name the chambers of the heart, heart valves, and major vessels associated with each chamber
Right atrium: chamber into which the Vena Cava empties, valve between it and the ventricle is the R Atrioventricular (tricuspid) valve R. Ventricle: chamber that pumps blood through the R semilunar valve (pulmonic semilunar) to the Pulmonary artery that goes to the lungs L. Atria: chamber into which the pulmonary vein empties, valve between it and the L Ventricle is the L Atrioventricular (bicuspid/mitral) valve L. Ventricle: chamber that pumps blood through the L semilunar (aortic) valve to the Aorta`
Understand the pathway of electrical conduction through the heart
SA node, intranodal and intraatrial fibers, AV node, Bundle of His, R and L Bundle Branches, Purkinje Fibers
What is the order of transmission of the electrical impulses of the heart?
SA node, intranodal and intraatrial fibers, AV node, Bundle of His, R and L Bundle Branches, Purkinje Fibers
What is the order of transmission of the electrical impulses throughout the heart
SA node, intranodal and intraatrial fibers, AV node, Bundle of His, R and L Bundle Branches, Purkinje Fibers (P, QRS, and then T waves)
specialized myocardial cells in the wall of the right atrium; pacemaker of the heart
Sinoatrial node (SA node)
Heart sounds
Sounds are associated with the closing of heart valves.
Describe the mechanism underlying heart sounds
Sounds are associated with the closing of heart valves. The first sound occurs as the AV valve closes (ventricular pressure is higher than atrial pressure) and tends to be louder, longer, and more resonant than the second sound. The second is from when the SL valve closes (beginning of ventricular relaxation) and is short and sharp sounding.
Understand the cardiac cycle: sequence of events encompassing one complete contraction and relaxation of the atria and ventricles of the heart
Systole: period when either the ventricles or the atria are contracting Diastole: period of the cardiac cycle when either the ventricles or the atria are relaxing Cardiac rate: beats per minute
What does the electrocardiogram represent
The electrocardiogram represents the transmission of the electrical impulses through the heart that control the relaxation and contraction of the different chambers of the heart.
How does the sympathetic nervous system affect vascular control during exercise?
The sympathetic nervous system controls the contractility of the heart determining the ESV value. It controls the strength and frequency of the contractions of the heart muscles.
What is the structure of capillaries that allow them to carry out their function?
Thin wall for easy exchange and a strong resistance to flow
How is heart rate in exercise affected by training?
Training prepares your body for the exercise and allows you to do the same exercise with a lower heart rate (less strain on your heart).
allow for the flow of blood through the heart; atrioventricular are between the atria and ventricles, and semilunar are between the ventricles and main vessels connected to them
Valves of the heart (atrioventricular and semilunar)
What are varicose veins?
Varicose veins are veins in which the valve is not working properly (is leaky). These veins fill with so much blood that they start to gorge out and become very visible on the skin.
What are the three homeostatic mechanisms?
Vasoconstriction 2) Formation of a platelet plug 3) Production of a web of fibrin proteins around the platelet plug-normally platelets are kept apart due to protacyclin
Be able to trace the blood flow through the major anatomical landmarks of the heart.
Vena Cava, Right atrium, right atrioventricular (tricuspid) valve, right ventricle, right semilunar (pulmonic semilunar) valve, pulmonary artery, pulmonary vein, left atrium, left atrioventricular (bicuspid/mitral) valve, left ventrical, left semilunar (aortic) valve, aorta
blood through the major anatomical landmarks of the heart:
Vena Cava, Right atrium, right atrioventricular (tricuspid) valve, right ventricle, right semilunar (pulmonic semilunar) valve, pulmonary artery, pulmonary vein, left atrium, left atrioventricular (bicuspid/mitral) valve, left ventrical, left semilunar (aortic) valve, aorta
List the steps shared in common by the intrinsic and extrinsic clotting pathways.
Vessel injury; collagen ends exposed; platelet adhesion to collagen; release reaction; aggregation of platelets; and platelet plug formation
What are the factors that contribute to stroke volume?
actors that contribute to stroke volume are end diastolic volume (the amount of blood in the ventricle when it is full) and end systolic volume (amount of blood left in the ventricle at the end of injection) SV = EDV - ESV
bodily fluid that is composed of formed elements and plasma
blood
45—50% of blood volume contains erythrocytes leukocytes and thrombocytes Plasma and plasma proteins (albumins, globulins, and fibrinogen): 50-55% of blood volume contains water and solutes/particles
formed elements
composed of three layers (epicardium, myocardium, endocardium)
heart wall
a loose fitting sac with dense fibrous connective tissue that encloses the heart
parietal pericardium
atrial and ventricular relaxation
t wave phases
What is the structural differences between arteries, arterioles, capillaries, venules, and veins?
veins? Arteries: largest diameter, greatest amount of elastic tissue, smaller amount of smooth muscle compared to med & smaller arteries (large elastic Arterioles: largest wall thickness relative to diameter, large amounts of smooth muscle, smaller amounts of elastic tissue compared to large (muscular and distributing) Capillaries: composed solely of the tunica intima, only one layer of cells (exchange) Venules: structurally similar to capillaries, few smooth muscle cells (capacity) Veins: thin tissue layers, small amounts of smooth muscle, presence of valves in 2 mm diameter of vessels or greater (capacity)