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Questions and Answers
What is one of the primary functions of blood?
What is one of the primary functions of blood?
How does blood help maintain homeostasis in the body?
How does blood help maintain homeostasis in the body?
Which statement accurately describes blood as a connective tissue?
Which statement accurately describes blood as a connective tissue?
Which component is NOT part of the blood's functions?
Which component is NOT part of the blood's functions?
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What role does blood NOT play in the cardiovascular system?
What role does blood NOT play in the cardiovascular system?
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What is a primary component measured in a Complete Blood Count (CBC)?
What is a primary component measured in a Complete Blood Count (CBC)?
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Which of the following correctly describes the sinoatrial (SA) node?
Which of the following correctly describes the sinoatrial (SA) node?
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What is a characteristic of anemia?
What is a characteristic of anemia?
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What is the role of the Purkinje fibers in the heart's conducting system?
What is the role of the Purkinje fibers in the heart's conducting system?
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Which of the following is NOT a type of white blood cell (WBC) measured in a differential count?
Which of the following is NOT a type of white blood cell (WBC) measured in a differential count?
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What characterizes atrial fibrillation?
What characterizes atrial fibrillation?
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Which stage of the cardiac cycle involves active ventricular filling?
Which stage of the cardiac cycle involves active ventricular filling?
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What is a common consequence of ventricular fibrillation?
What is a common consequence of ventricular fibrillation?
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What is the primary function of veins in the circulatory system?
What is the primary function of veins in the circulatory system?
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What does the electrocardiogram (ECG) measure?
What does the electrocardiogram (ECG) measure?
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What happens during ventricular diastole?
What happens during ventricular diastole?
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What is an AV node block?
What is an AV node block?
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Which of the following is NOT a major function of the circulatory system?
Which of the following is NOT a major function of the circulatory system?
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What is the primary function of the circulatory system?
What is the primary function of the circulatory system?
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How does blood pressure change as blood moves through different types of blood vessels?
How does blood pressure change as blood moves through different types of blood vessels?
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What factor primarily affects the velocity of blood flow in the circulatory system?
What factor primarily affects the velocity of blood flow in the circulatory system?
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What happens to blood flow in the capillaries compared to the aorta?
What happens to blood flow in the capillaries compared to the aorta?
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What is a factor that does NOT affect systemic circulation function?
What is a factor that does NOT affect systemic circulation function?
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What relationship exists between vessel diameter and resistance to blood flow?
What relationship exists between vessel diameter and resistance to blood flow?
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What is the unit of measurement for blood pressure?
What is the unit of measurement for blood pressure?
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What role does the circulatory system play in regulating blood pressure?
What role does the circulatory system play in regulating blood pressure?
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What primarily drives the movement of particles during capillary exchange?
What primarily drives the movement of particles during capillary exchange?
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Which of the following organs exhibits autoregulation of blood flow?
Which of the following organs exhibits autoregulation of blood flow?
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What physiological response occurs when blood pressure is high?
What physiological response occurs when blood pressure is high?
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Which mechanism is activated during significant physical activity to help regulate blood pressure?
Which mechanism is activated during significant physical activity to help regulate blood pressure?
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What triggers the chemoreceptor reflexes located in the carotid bodies?
What triggers the chemoreceptor reflexes located in the carotid bodies?
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What is the main consequence of prolonged lack of blood flow to cardiac muscle?
What is the main consequence of prolonged lack of blood flow to cardiac muscle?
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What condition is characterized by chest pain due to reduced blood supply to cardiac muscle?
What condition is characterized by chest pain due to reduced blood supply to cardiac muscle?
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Atherosclerosis primarily affects which type of arteries?
Atherosclerosis primarily affects which type of arteries?
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What is the primary role of baroreceptors in regulating blood pressure?
What is the primary role of baroreceptors in regulating blood pressure?
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The renin-angiotensin-aldosterone system is involved in which type of blood pressure regulation?
The renin-angiotensin-aldosterone system is involved in which type of blood pressure regulation?
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What is the main composition of plaques formed in atherosclerosis?
What is the main composition of plaques formed in atherosclerosis?
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What physiological response is responsible for temporary chest pain associated with angina pectoris?
What physiological response is responsible for temporary chest pain associated with angina pectoris?
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Which mechanism is primarily activated due to decreased blood flow to the brain?
Which mechanism is primarily activated due to decreased blood flow to the brain?
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What is the normal platelet count range per microliter of blood necessary for effective clot formation?
What is the normal platelet count range per microliter of blood necessary for effective clot formation?
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Which two clotting factors are proteins in the blood that significantly contribute to the clotting process?
Which two clotting factors are proteins in the blood that significantly contribute to the clotting process?
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Which blood test measures how long it takes for the blood to initiate clotting?
Which blood test measures how long it takes for the blood to initiate clotting?
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What is the normal range for Activated Partial Thromboplastin Time (APTT), which evaluates the intrinsic pathway of coagulation?
What is the normal range for Activated Partial Thromboplastin Time (APTT), which evaluates the intrinsic pathway of coagulation?
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What happens in the absence of sufficient blood clotting factors during an injury?
What happens in the absence of sufficient blood clotting factors during an injury?
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Which of the following components is NOT part of the conducting system of the heart?
Which of the following components is NOT part of the conducting system of the heart?
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In a complete blood count (CBC), a reduced hemoglobin level indicates which condition?
In a complete blood count (CBC), a reduced hemoglobin level indicates which condition?
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What delay occurs in the cardiac conduction system that allows for proper filling of the ventricles?
What delay occurs in the cardiac conduction system that allows for proper filling of the ventricles?
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Which type of white blood cell is primarily responsible for combating parasitic infections?
Which type of white blood cell is primarily responsible for combating parasitic infections?
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What is the primary effect of a disruption in the heart's conducting system?
What is the primary effect of a disruption in the heart's conducting system?
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What occurs during ventricular systole of the cardiac cycle?
What occurs during ventricular systole of the cardiac cycle?
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What characterizes ventricular fibrillation?
What characterizes ventricular fibrillation?
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Which statement is true regarding the AV node block?
Which statement is true regarding the AV node block?
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Which of the following is NOT a function of the circulatory system?
Which of the following is NOT a function of the circulatory system?
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What describes the role of capillaries within the circulatory system?
What describes the role of capillaries within the circulatory system?
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Which event initiates the cardiac cycle?
Which event initiates the cardiac cycle?
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During which phase of the cardiac cycle is isovolumetric relaxation observed?
During which phase of the cardiac cycle is isovolumetric relaxation observed?
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What defines the conduction pathways in arrhythmias?
What defines the conduction pathways in arrhythmias?
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What is the relationship between blood vessel diameter and resistance to blood flow?
What is the relationship between blood vessel diameter and resistance to blood flow?
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Which factor has the most significant effect on blood pressure as it moves through systemic circulation?
Which factor has the most significant effect on blood pressure as it moves through systemic circulation?
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Which statement accurately describes the velocity of blood flow in relation to cross-sectional area?
Which statement accurately describes the velocity of blood flow in relation to cross-sectional area?
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How does the blood pressure in the capillaries compare to that in the aorta?
How does the blood pressure in the capillaries compare to that in the aorta?
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Which of the following functions does NOT pertain to the circulatory system?
Which of the following functions does NOT pertain to the circulatory system?
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What does blood pressure measure?
What does blood pressure measure?
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What is the primary function of the systemic circulation in the context of the circulatory system?
What is the primary function of the systemic circulation in the context of the circulatory system?
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Which description accurately depicts the effect of gravity on blood pressure?
Which description accurately depicts the effect of gravity on blood pressure?
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What primarily drives the mechanisms of short-term regulation of blood pressure?
What primarily drives the mechanisms of short-term regulation of blood pressure?
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What is the primary cause of angina pectoris?
What is the primary cause of angina pectoris?
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Which mechanism is responsible for the formation of plaques in atherosclerosis?
Which mechanism is responsible for the formation of plaques in atherosclerosis?
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During a myocardial infarction, what ultimately leads to cellular death in cardiac muscle?
During a myocardial infarction, what ultimately leads to cellular death in cardiac muscle?
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Which of the following organs does NOT exhibit autoregulation of blood flow?
Which of the following organs does NOT exhibit autoregulation of blood flow?
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What is the primary function of the renin-angiotensin-aldosterone mechanism?
What is the primary function of the renin-angiotensin-aldosterone mechanism?
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What physiological response occurs when there is a significant decrease in renal perfusion pressure?
What physiological response occurs when there is a significant decrease in renal perfusion pressure?
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What happens during the CNS ischemic response?
What happens during the CNS ischemic response?
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What role does the adrenal medullary mechanism play during stress?
What role does the adrenal medullary mechanism play during stress?
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Which statement best describes central chemoreceptor reflexes?
Which statement best describes central chemoreceptor reflexes?
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What physiological effect is primarily associated with increased metabolic activity in muscles?
What physiological effect is primarily associated with increased metabolic activity in muscles?
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What is the effect of baroreceptor activation in response to low blood pressure?
What is the effect of baroreceptor activation in response to low blood pressure?
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How does fluid shift mechanism affect blood pressure regulation?
How does fluid shift mechanism affect blood pressure regulation?
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What condition is primarily characterized by the deposition of fatty materials in arterial walls?
What condition is primarily characterized by the deposition of fatty materials in arterial walls?
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Study Notes
Blood Composition
- Blood is a type of connective tissue.
- Composed of cells and cell fragments in a liquid matrix.
Blood Functions
- Transports gases, nutrients, and waste products.
- Transports processed molecules.
- Transports regulatory molecules.
- Regulates pH and osmosis.
- Maintains body temperature.
- Protects against foreign substances.
- Complete Blood Count (CBC) is a test. Includes:
- Red Blood Cell (RBC) count
- Hemoglobin and hematocrit measurements
- White blood cell (WBC) count (total WBC)
- Differential WBC count
- Comprised of five types of WBC: neutrophils, lymphocytes, monocytes, basophils, and eosinophils
Anemia
- Anemia is a reduction in the proportion of red blood cells.
- Can be caused by a reduction in hemoglobin, hematocrit or RBC count.
Heart Anatomy
- The heart is a four-chambered organ.
Blood Flow Through the Heart
- Blood enters the heart through the right atrium.
- It is then pumped to the right ventricle, which pumps it through the pulmonary artery to the lungs.
- The blood returns to the heart through the pulmonary veins.
- It enters the left atrium and is pumped to the left ventricle and out through the aorta.
- The blood then travels through the rest of the body before returning to the heart
Conducting System of the Heart
- The conducting system of the heart is a network of specialized muscle cells that conduct electrical impulses.
- This regulates heartbeats.
- Composed of:
- Two nodes
- Sinoatrial (SA) node: Located at junction of the superior vena cava and the right atrium. This is the "pacemaker" of the heart.
- Atrioventricular (AV) node: Located in the interatrial septum of the right atrium.
- Serves as a gatekeeper for the cardiac impulses that enter the ventricles.
- Conducting bundle
- Atrioventricular (AV) bundle, or Bundle of His: Conducts the electrical impulse rapidly from the AV node to the right and left bundle branches.
- Right and Left Bundle Branches
- Purkinje fibers: Responsible for conducting the electrical impulse through the ventricular chambers, which leads to their contraction.
- Right and Left Bundle Branches
- Atrioventricular (AV) bundle, or Bundle of His: Conducts the electrical impulse rapidly from the AV node to the right and left bundle branches.
- Two nodes
Arrythmia
- An abnormal cardiac rhythm.
- Can occur due to abnormal conduction pathways.
AV Node Block
- Interruption or delay of electrical conduction from the atria to the ventricles.
- Caused by conduction system abnormalities in the AV node or the His-Purkinje system.
Atrial Fibrillation
- Irregular timing, ventricles are constantly stimulated by the atria.
Ventricular Fibrillation
- No rhythmic contraction of the myocardium. This means that the ventricular muscle contracts asynchronously.
Electrocardiogram (ECG)
- Records electrical activity of the heart.
- Action potentials conducted through the myocardium during the cardiac cycle produce electrical currents that can be measured at the body surface.
Cardiac Cycle
- The cardiac cycle refers to the repetitive pumping process that starts with the onset of cardiac muscle contraction and ends with the beginning of the next contraction.
Cardiac Cycle: Systole and Diastole
- Systole refers to the contraction of the heart chambers.
- Diastole refers to the relaxation of the heart chambers.
Cardiac Cycle Phases
- Atrial systole: Active ventricular filling.
- Ventricular systole: Period of isovolumetric contraction
- Ventricular systole: Period of ejection
- Ventricular diastole: Period of isovolumetric relaxation
- Ventricular diastole: Passive ventricular filling
Blood Vessels
- Blood vessels are organized into two sets:
- Pulmonary vessels
- Systemic vessels
Vessel Anatomy
- Arteries carry blood away from the heart to capillaries.
- Capillaries exchange materials between the blood and tissues.
- Veins deliver blood from capillaries back to the heart.
Functions of the Circulatory System
- Carries blood.
- Exchanges nutrients, waste products, and gases with tissues.
- Transports substances.
- Helps regulate blood pressure.
- Directs blood flow to tissues.
Blood Pressure
- Blood pressure measures the force blood exerts against the blood vessel walls.
- Unit: millimeters of mercury (mmHg).
- Measured using the auscultatory method.
Physiology of the Systemic Circulation
- The primary function of the circulatory system is distribution.
- This ensures that substances like oxygen, carbon dioxide, nutrients, hormones, and others are transported efficiently throughout the body.
- Factors that affect systemic circulation function:
- Cross-sectional area of blood vessels
- Pressure and resistance
- Pulse and pulse pressure
- Capillary exchange and regulation of interstitial fluid volume
- Functional characteristics of veins
- Blood pressure and the effect of gravity
Cross-Sectional Area of Blood Vessels
- The velocity of blood flow is inversely proportional to its cross-sectional area.
- Aorta: Has the greatest velocity. Has a small total cross-sectional area.
- Capillaries: Have a large total cross-sectional area. Have low blood flow.
Pressure and Resistance
- The decrease in blood pressure in each part of the systemic circulation is directly proportional to the resistance to blood flow.
- Resistance to flow is associated with the diameter of the vessel
- ↓ Vessel diameter = ↑ Resistance
Capillary Exchange and Regulation of Interstitial Fluid Volume
- This driven by:
- Net filtration pressure
- Net hydrostatic pressure
- Net osmotic pressure
Local Control of Blood Flow in Tissues
- Blood flow is unequal in all tissue in the body.
- Blood flow to the brain, kidneys, and liver is high.
- Blood flow to resting skeletal muscles is not high.
- Local control of blood flow is achieved by the periodic relaxation and contraction of precapillary sphincters which regulates blood flow through capillary networks of tissues.
Autoregulation of Blood Flow
- Autoregulation is the maintenance of blood flow to tissues.
- This blood flow remains constant (or within normal range) over a wide range of pressure.
- Organs and tissue that exhibit autoregulation include the heart, brain, and kidneys.
- If perfusion pressure to the heart is suddenly decreased, compensatory vasodilation of the arterioles will occur to maintain a constant flow.
Long-Term Local Blood Flow
- An example of long-term local blood flow:
- Increased metabolic activity of muscle (e.g., in athletes).
- This leads to an increase in the diameter and number of capillaries in the tissues.
- Local blood flow increases.
Short-Term Regulation of Blood Pressure
- Mechanisms include:
- Baroreceptor reflexes
- Adrenal medullary mechanism
- Chemoreceptor reflexes
- Central nervous system ischemic response
Short-Term Regulation of Blood Pressure: Baroreceptors
- Sensory receptors sensitive to stretch.
- Found along the walls of large arteries in the neck and thorax.
- For example: The carotid sinus reflex and the aortic arch reflex.
- Baroreceptor reflex examples: - High BP: Increased BP → Increased stretch → Dilation of blood vessels to maintain normal BP (prevent hypertension) - Low BP: Decreased BP → Decreased stretch → Constriction of blood vessels to maintain normal BP (Prevent hypotension)
Short-Term Regulation of Blood Pressure: Adrenal Medullary Mechanism
- Activated by substantial increase in sympathetic stimulation of the heart and blood vessels.
- Releases Epinephrine and Norepinephrine into the bloodstream.
- Activated during:
- Large decreases in blood pressure.
- Sudden and substantial increase in physical activity.
- Other stressful conditions
Short-Term Regulation of Blood Pressure: Chemoreceptor Reflexes
- Located in the carotid bodies and aortic bodies.
- This is a small organ found near the carotid sinuses.
- Examples:
- Increased blood CO2: Decreased blood pH → Increased breathing rate (to blow off CO2).
Short-Term Regulation of Blood Pressure: CNS Ischemic Response
- This occurs in response to lack of blood flow to the medulla oblongata of the brain.
- Functions primarily in response to emergency situations.
- For example: When blood blood flow to the brain is severely restricted or when BP falls below approximately 50 mmHg.
Long-Term Regulation of Blood Pressure
- Mechanisms include:
- Renin-angiotensin-aldosterone mechanism (RAAS)
- Antidiuretic hormone (vasopressin) mechanism
- Atrial natriuretic mechanism
- Fluid shift mechanism
- Stress-relaxation response
Atherosclerosis
- Deposition of material in the walls of arteries, which forms distinct plaques.
- Primarily affects medium to larger arteries, including the coronary arteries.
- Plaques form when macrophages containing cholesterol accumulate in the smooth muscle cells of the blood vessels.
- Enlarged plaques consist of smooth muscle cells, white blood cells, lipids (including cholesterol), and fibrous connective tissue, as well as calcium deposits.
Angina Pectoris
-
Chest pain resulting from a reduced blood supply to cardiac muscle.
-
The pain is temporary and little permanent change or damage results if blood flow is restored.
-
Characterized by chest discomfort at the sternum which is often described as heaviness, pressure, or moderately severe pain.
-
Caused by narrowed and hardened coronary arterial walls.
-
Reduced blood flow → reduced supply of O2 to cardiac muscle cells → limited anaerobic respiration of the cardiac muscle → reduced pH in the affected areas of the heart → stimulates pain receptors.
Myocardial Infarction (MI)
- Results when there’s prolonged lack of blood flow to a part of the cardiac muscle.
- This leads to a lack of O2 and ultimately cellular death.
- Symptoms of an MI include:
- Chest pain that radiates into the left shoulder and arm.
- Shortness of breath.
- Nausea.
- Vomiting.
- Sweating.
Blood Function
- Blood transports essential materials like oxygen, carbon dioxide, nutrients, waste products, hormones, and enzymes throughout the body.
- Blood helps regulate the pH balance of the body, maintaining a pH of 7.35 to 7.45.
- Blood is crucial for maintaining body temperature, working in conjunction with the skin.
- Blood defends the body against foreign substances like microorganisms and toxins through its immune system components.
- Blood clotting is essential to prevent excessive blood loss from injuries.
Blood Tests
- Platelet count is a measure of the number of platelets in a microliter of blood, with a normal range of 150,000 to 450,000 platelets.
- Prothrombin time (PT) and Activated Partial Thromboplastin Time (APTT) measure the time it takes for blood to clot. Normal PT is 10 to 13 seconds, while normal APTT is 25 to 35 seconds.
- Clotting factors VIII and IX are proteins involved in blood clotting, helping to stop bleeding.
- Complete Blood Count (CBC) includes red blood cell (RBC) count, hemoglobin (Hb) and hematocrit (Hct) measurements, white blood cell (WBC) count (total WBC), and differential WBC count.
- Anemia is characterized by a reduction in either the red blood cell count, hemoglobin, or hematocrit, leading to a decrease in the oxygen-carrying capacity of the blood.
Heart Anatomy
- The heart is a four-chambered organ responsible for pumping blood throughout the body.
- The heart has two upper chambers called atria and two lower chambers called ventricles.
- The heart is made up of cardiac muscle, which contracts rhythmically to pump blood.
Conducting System of the Heart
- The conducting system of the heart relays electrical signals throughout the heart, coordinating its rhythmic contraction.
- The SA Node (Sinoatrial Node) is known as the pacemaker of the heart, initiating the electrical signal.
- The AV Node (Atrioventricular Node) delays the electrical signal slightly, allowing the atria to contract and fill the ventricles with blood before the ventricles contract.
- The AV Bundle (Bundle of His) conducts the electrical signal from the AV Node to the ventricles.
- The right and left bundle branches transmit the signal to the ventricles, and the Purkinje fibers distribute the signal to the ventricular muscle cells.
- Disruptions in the conducting system can result in arrhythmias, which are abnormal heart rhythms.
Heart Pathophysiology
- Arrhythmias are characterized by an irregular heartbeat due to abnormal conduction pathways or patterns.
- AV Node Block occurs when the electrical signal is interrupted or delayed from the atria to the ventricles.
- Atrial fibrillation is a type of arrhythmia where the atria contract irregularly, causing erratic ventricular contractions.
- Ventricular fibrillation is a dangerous arrhythmia where the ventricles contract chaotically, resulting in the heart's inability to pump blood effectively.
Electrocardiogram (ECG)
- An electrocardiogram (ECG) records the electrical activity of the heart, providing valuable information about its function.
- ECGs measure the electrical currents generated by the heart during its regular activity, revealing patterns that indicate the heart's health.
Cardiac Cycle
- The cardiac cycle is the repetitive sequence of events that occurs during one heartbeat.
- The cycle includes systole (contraction) and diastole (relaxation) of heart chambers.
- Atrial systole expels blood from the atria into the ventricles.
- Ventricular systole involves ventricular contraction, pushing blood into the aorta and pulmonary arteries.
- Ventricular diastole involves ventricular relaxation and filling with blood from the atria.
Blood Vessels Anatomy
- Blood vessels form a network that carries blood throughout the body.
- Arteries carry oxygenated blood away from the heart.
- Veins carry deoxygenated blood back to the heart.
- Capillaries are tiny blood vessels that allow for the exchange of materials between the blood and tissues.
Functions of the Circulatory System
- The circulatory system transports blood, oxygen, carbon dioxide, nutrients, waste products, and other substances.
- It helps regulate blood pressure and directs blood flow to different tissues based on their needs.
Blood Pressure
- Blood pressure measures the force of blood against the walls of blood vessels, expressed in millimeters of mercury (mmHg).
- The auscultatory method is commonly used to measure blood pressure using a stethoscope and sphygmomanometer.
Systemic Circulation Physiology
- The systemic circulation delivers oxygenated blood from the heart to the body's tissues and returns deoxygenated blood to the heart.
- Factors affecting systemic circulation include:
- Cross-sectional area of blood vessels: Velocity is inversely proportional to cross-sectional area.
- Pressure and resistance: Blood pressure decreases as blood flows through different vessel types due to resistance.
- Pulse and pulse pressure: Pulse measures the rhythmic expansion and contraction of arteries as blood is pumped.
- Capillary exchange: Capillaries facilitate exchange of materials between blood and tissues, regulated by factors like hydrostatic and osmotic pressure.
- Functional characteristics of veins: Veins are responsible for returning blood to the heart.
- Blood pressure and gravity: Gravity influences blood pressure, particularly in the lower extremities.
Local Control of Blood Flow
- Blood flow is not uniform throughout the body, varying based on tissue needs.
- Local control of blood flow involves periodic relaxation and contraction of precapillary sphincters, which regulate blood flow through capillary networks.
Autoregulation of Blood Flow
- Autoregulation maintains constant blood flow to organs over a wide range of systemic pressures.
- Organs like the heart, brain, and kidneys exhibit autoregulation.
Long-Term Local Blood Flow
- Tissue metabolic activity can influence long-term blood flow regulation.
- Increased activity, like in athletes, leads to increased capillary diameter and number, enhancing local blood flow.
Short-Term Regulation of Blood Pressure: Mechanisms
- Baroreceptor reflex: Baroreceptors, located in the walls of large arteries, detect changes in blood pressure and trigger appropriate responses to maintain normal pressure.
- Adrenal medullary mechanism: The adrenal glands release epinephrine and norepinephrine in response to stress or significant changes in blood pressure, causing vasoconstriction and increased heart rate.
- Chemoreceptor reflexes: Chemoreceptors located in the carotid bodies and aortic bodies respond to changes in blood gases and pH, influencing breathing rate and blood pressure.
- Central nervous system ischemic response: This reflex is activated when blood flow to the medulla oblongata is severely restricted, causing an increase in blood pressure to ensure brain perfusion.
Long-Term Regulation of Blood Pressure: Mechanisms
- Renin-angiotensin-aldosterone system (RAAS): This system plays a crucial role in maintaining blood pressure by regulating sodium and water retention.
- Antidiuretic hormone (ADH) mechanism: ADH causes vasoconstriction and water reabsorption, increasing blood volume and pressure.
- Atrial natriuretic mechanism: This mechanism promotes sodium and water excretion, reducing blood volume and pressure.
- Fluid shift mechanism: This mechanism involves shifting fluids between the vascular and interstitial compartments, influencing blood volume and pressure.
- Stress-relaxation response: Blood vessels adjust their tension in response to changes in blood pressure, promoting long-term regulation.
Atherosclerosis
- Atherosclerosis is characterized by the buildup of atherosclerotic plaques in the walls of arteries, narrowing the vessel lumen and impeding blood flow.
- These plaques consist of smooth muscle cells, white blood cells, lipids (including cholesterol), fibrous connective tissue, and calcium deposits.
Angina Pectoris
- Angina pectoris is chest pain caused by reduced blood flow to the heart muscle.
- It is usually temporary, resolving when blood flow returns, but can indicate underlying coronary artery disease.
- Angina typically involves chest discomfort around the sternum, described as pressure, heaviness, or pain.
Myocardial Infarction (MI)
- A myocardial infarction (MI), or heart attack, occurs when prolonged blockage of a coronary artery leads to heart muscle cell death due to oxygen deprivation.
- Symptoms of MI include chest pain radiating to the left arm and shoulder, shortness of breath, nausea, vomiting, and sweating.
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Description
Test your knowledge on blood composition, functions, and the anatomy of the heart. This quiz covers how blood works in the body, the significance of Complete Blood Count (CBC), and the critical role of the heart in circulation. Understand vital concepts related to blood flow and conditions like anemia.
