ANAT1052 Cardiovascular System PDF

4 CARDIOVASCULAR SYSTEM 1. State the components and the overall function of the cardiovascular system. Component Description Function A muscular pump Heart located in the thoracic Propels blood through the blood vessels, maintaining circulation...

4 CARDIOVASCULAR SYSTEM 1. State the components and the overall function of the cardiovascular system. Component Description Function A muscular pump Heart located in the thoracic Propels blood through the blood vessels, maintaining circulation throughout the body. cavity. - Arteries: Carry blood AWAY from the heart Includes arteries, veins, - Veins: Carry blood BACK to the heart. Blood Vessels and capillaries. - Capillaries: Facilitate the exchange of oxygen, nutrients, and wastes between blood and tissues. Overall Function - “Bulk Transport System”: circulates blood to deliver oxygen and nutrients to tissues, remove wastes, and maintain homeostasis. -Regulates body temperature, fluid balance, and pH levels, and supports hormone transportation. 2. State the location, size and position of the heart. Characteristic Description Location Thoracic cavity, in the mediastinum, between the lungs. Size About the size of a fist, weighs around 300 grams. Tilts slightly to the left, with two-thirds of its mass on the left side of the median Position plane. 3. Identify the location of the apex and base of the heart. Part of the Heart Description Lower pointed end of the heart, located just Apex above the diaphragm. Broad, superior part of the heart where large Base blood vessels attach. ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 1 4. Describe and state the function of the pericardium: Pericardial Description and Function Component Outer fibrous layer that Parietal Pericardium provides protection and structure to the heart. Inner layer (also called Visceral Pericardium epicardium) that covers the heart surface closely. Space between the parietal and visceral pericardium Pericardial Cavity filled with fluid to reduce friction during heartbeats. 5. Describe and state the functions of the layers that make up the wall of the heart: Layer Description and Function Outer layer that protects the heart; composed Epicardium of epithelial and connective tissue. Thick, muscular middle layer responsible for Myocardium contracting and pumping blood. Inner lining of the heart chambers and valves, Endocardium ensures smooth blood flow within the heart. 6. Differentiate between arteries and veins in terms of direction of blood flow. Type of Vessel Direction of Blood Flow Arteries Carry blood away from the heart; usually oxygenated, ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 2 Type of Vessel Direction of Blood Flow except for the pulmonary arteries. Carry blood toward the heart; Veins usually deoxygenated, except for the pulmonary veins. 7. Differentiate between the systemic and pulmonary circulation of blood. Type of Circulation Function Systemic Carries oxygenated blood from the left side of the heart to the body tissues and returns deoxygenated Circulation blood to the heart. Pulmonary Carries deoxygenated blood from the right side of the heart to the lungs for oxygenation, then returns Circulation oxygenated blood to the heart. 8. Briefly describe the Hepatic-Portal circulation of blood. Description Function Hepatic-Portal Blood from the gastrointestinal tract passes through the liver for nutrient absorption and detoxification Circulation before entering general circulation. 9. Identify, describe and state the functions of the chambers of the heart: Chamber Description and Function Receives deoxygenated blood from the body via the superior and inferior vena Right Atrium cava. Right Ventricle Pumps deoxygenated blood into the pulmonary arteries to the lungs. ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 3 Chamber Description and Function Left Atrium Receives oxygenated blood from the lungs via the pulmonary veins. Left Ventricle Pumps oxygenated blood through the aorta to the body. 10. Identify, describe and state the function of the heart valves: Valve Description and Function Atrioventricular (AV) Controls blood flow between atria and ventricles, preventing backflow into the atria during ventricular Valve contraction. Tricuspid Valve Right AV valve with three cusps, located between the right atrium and right ventricle. Bicuspid (Mitral) Valve Left AV valve with two cusps, located between the left atrium and left ventricle. Tendinous cords that anchor AV valve cusps to papillary muscles, preventing inversion during Chordae Tendineae ventricular contraction. Semilunar Valves Prevent backflow from arteries into ventricles after blood is ejected. Pulmonary Valve Controls flow from the right ventricle into the pulmonary trunk. Aortic Valve Controls flow from the left ventricle into the aorta. 11. Describe the action of heart valves and how they promote the movement of blood through the heart. Valve Action How They Promote Blood Flow Open during atrial systole to allow blood flow from atria to ventricles; close during ventricular systole to prevent AV Valves backflow. Semilunar Open when ventricular pressure exceeds arterial pressure, allowing blood ejection into the pulmonary trunk and Valves aorta; close to prevent backflow into ventricles during diastole. 12. Diastole vs. Systole Term Description Diastole The phase when the heart muscle relaxes and the chambers fill with blood. Systole The phase when the heart contracts, pumping blood out of the chambers. ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 4 13. Blood Flow Through the Heart Step Pathway From the superior and 1. Blood enters the inferior venae cavae right atrium (deoxygenated blood). 2. Blood flows through the Into the right ventricle. tricuspid valve Through the pulmonary valve into the pulmonary 3. Right ventricle trunk and pulmonary pumps blood arteries, to the lungs (for oxygenation). 4. Oxygenated blood returns to Via the pulmonary veins. the left atrium 5. Blood flows through the mitral Into the left ventricle. valve Through the aortic valve 6. Left ventricle into the aorta, to be pumps blood distributed to the rest of the body. 14. Coronary Arteries and Cardiac Veins Vessel Location Function Branch from the aorta; Supply oxygenated blood to Coronary Arteries travel across the surface the heart muscle. of the heart. Drain into the coronary Return deoxygenated blood Cardiac Veins sinus, which empties from the heart muscle back into the right atrium. to the right atrium. ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 5 15. Classifications of Blood Vessels Type of Blood Description Vessel Arteries Carry blood away from the heart Arterioles Small branches of arteries that lead to capillaries. Capillaries Microscopic vessels where the exchange of nutrients and gases occurs between blood and tissues. Venules Small veins that collect blood from capillaries. Veins Carry blood toward the heart, usually deoxygenated. Carries nutrient-rich blood from the digestive organs to the liver for processing before returning to the Hepatic Portal Vein heart. 16. Structural Components of a Blood Vessel Layer Description Tunica Externa Outer layer composed of connective tissue, anchors the vessel to surrounding tissues. (Adventitia) Middle layer composed of smooth muscle and elastic tissue, responsible for vasoconstriction and Tunica Media vasodilation. Inner layer composed of endothelium and connective tissue, providing a smooth surface for blood Tunica Interna (Intima) flow. 17. Structure and Functions of Arteries and Veins Feature Arteries Veins Thick, muscular, and elastic walls to Thinner walls, less muscular, contain Structure withstand high pressure. valves to prevent backflow. Carry blood away from the heart Carry blood toward the heart, often Function under high pressure. under lower pressure. ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 6 18. Structure and Function of Capillaries Structure Function Very thin walls (just one cell thick, composed of Facilitate the exchange of oxygen, nutrients, carbon dioxide, and waste endothelium). products between blood and tissues. 19. Capillary Bed vs. Microcirculation Term Description Network of capillaries branching from arterioles, allowing the exchange of substances between blood and Capillary Bed tissues. Microcirculation The circulation of blood in the smallest blood vessels (arterioles, capillaries, venules) within tissues. 20. Role of Pre-capillary Sphincters Function Pre-capillary sphincters are rings of smooth muscle that regulate blood flow into capillary beds, controlling tissue perfusion (flow of blood through the body’s tissues) 21. Blood Reservoir (Capacitance Vessel) Term Description Veins are often referred to as capacitance vessels because Blood Reservoir they can hold large volumes of (Capacitance Vessel) blood and accommodate changes in blood volume. ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 7 22. Factors Promoting the Return of Blood Through Veins Factor Description One-way valves in veins prevent Valves backflow, ensuring blood moves toward the heart. Skeletal muscles contract and squeeze veins, pushing blood Muscle Contraction toward the heart (muscle pump mechanism). During inhalation, pressure changes in the thoracic and Respiratory Action abdominal cavities create a suction effect, drawing blood to the heart (thoracic pump). Veins have thinner, flexible walls that allow them to expand and Vein Structure accommodate varying blood volumes, facilitating return to the heart. 23. Major Arteries of the Body Artery Location Neck; supplies the head and Common Carotid brain. Kidneys; supplies the kidneys Renal with blood. Beneath the clavicle; supplies Subclavian the arms. Abdominal cavity; supplies Celiac stomach, liver, spleen. Right side; branches into right Brachiocephalic subclavian and carotid. ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 8 Artery Location Hepatic Supplies the liver. Armpit region; continuation of Axillary the subclavian artery. Splenic Supplies the spleen. Upper arm; continuation of the Brachial axillary artery. Supplies the small intestine and Superior Mesenteric proximal colon. Radial Lateral forearm. Inferior Mesenteric Supplies the distal colon. Ulnar Medial forearm. Pelvic region; splits into external Common Iliac and internal iliac. Main artery from the heart, Aorta running through the chest and abdomen. External Iliac Supplies the lower limb. Curve of the aorta; gives rise to Aortic Arch major upper body arteries. Internal Iliac Supplies the pelvic organs. Continuation of the aorta below Abdominal Aorta the diaphragm. Thigh region; supplies the lower Femoral limb. Carries blood from the right Pulmonary ventricle to the lungs. Behind the knee; supplies the Popliteal lower leg. Supplies blood to the heart Coronary muscle. ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 9 Artery Location Supplies the anterior Anterior Tibial compartment of the leg. 24. Major Veins of the Body Vein Location Drains blood from the head and External Jugular neck into the subclavian vein. Drains blood from the liver into Hepatic the inferior vena cava. Drains blood from the brain and Internal Jugular face into the subclavian vein. Carries nutrient-rich blood from Hepatic-Portal the digestive organs to the liver. Drains blood from the arms and Brachiocephalic head into the superior vena cava. Renal Drains blood from the kidneys. Drains blood from the arms into Subclavian the brachiocephalic vein. Drains blood from the small Superior Mesenteric intestine. Drains blood from the armpit Axillary and upper limb. Drains blood from the large Inferior Mesenteric intestine. Drains blood from the heart Cardiac muscle. Drains blood from the lower Common Iliac limbs into the inferior vena cava. Carries oxygenated blood from Pulmonary the lungs to the left atrium. ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 10 Vein Location Drains blood from the pelvic Internal Iliac organs. Drains blood from the upper Superior Vena Cava body into the right atrium. Drains blood from the lower External Iliac limbs. Drains blood from the lower Inferior Vena Cava body into the right atrium. Drains blood from the thigh Femoral region. Drains blood from the lateral Radial side of the forearm. Longest vein in the body, running Great Saphenous along the leg. Vein commonly used for drawing Median Cubital blood from the arm. Drains blood from the knee Popliteal region. Drains blood from the medial Ulnar side of the forearm. Drains blood from the front of Anterior Tibial the lower leg. 25. List the general functions of blood. Function Description Transport Transports oxygen, carbon dioxide, nutrients, hormones, and waste products throughout the body. Regulation Helps regulate body temperature, pH levels, and fluid balance. Provides defense against infections and diseases through white blood cells and antibodies, and initiates blood Protection clotting to prevent excessive bleeding. Homeostasis Maintains a stable internal environment by balancing electrolytes and fluids. ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 11 26. Blood Plasma vs. Formed Elements Component Description The liquid portion of blood, making up about 55%, composed of water, proteins, Blood Plasma nutrients, hormones, and waste products. The solid portion of blood, making up about 45%, including red blood cells, Formed Elements white blood cells, and platelets. 27. Percentages of Plasma and Formed Elements Percentage in Whole Component Blood Plasma ~55% Formed Elements ~45% 28. Approximate Liters of Blood in an Adult Approximate Volume of Gender Blood Female 4–5 liters Male 5–6 liters 29. pH of Whole Blood Measurement Range pH 7.35–7.45 (slightly alkaline) 30. Components of Blood Plasma Component Percentage or Description Water 91% Proteins 6–9 g/dL (Albumin, Globulins, Fibrinogen) Glucose, amino acids, lipids (cholesterol, fatty acids, triglycerides, and Nutrients phospholipids), vitamins, iron, and trace elements ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 12 Component Percentage or Description Salts formed of cations and anions of sodium, potassium, magnesium, Electrolytes calcium, and other elements Gases Oxygen, carbon dioxide, and nitrogen Hormones Insulin, thyroid hormone, estrogen, and all other hormones Nitrogenous Urea, uric acid, creatine, creatinine, bilirubin, ammonia wastes 31. Common Plasma Proteins and Their Functions Protein Function Maintains osmotic pressure and transports Albumin substances. Globulins Play roles in immunity, transport, and clotting. Fibrinogen Precursor to fibrin, essential for blood clotting. 32. Definition of Blood Serum Term Definition Blood plasma without the clotting factors Blood Serum (fibrinogen). 33. Types of Formed Elements in Blood Type Description -45% of whole blood - Two main functions: (1) to pick up oxygen Erythrocytes from the lungs and transport it to body Red blood cells (RBCs) tissues, and (2) to pick up carbon dioxide from the tissues and unload it in the lungs Leukocytes White blood -Provide immune response Buffy coat cells (WBCs) -Cell fragments that play a role in blood Platelets clotting. ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 13 34. Structure and Function of Erythrocytes Characteristic Description Biconcave, disc-shaped cells without a Structure nucleus, about 7.5 μm in diameter. Transport oxygen from the lungs to tissues Function and carbon dioxide from tissues to lungs. 35. Location of Erythrocyte Production Location Description Erythrocytes are produced in the red Red Bone Marrow bone marrow through the process called erythropoiesis. 36. Leukocytes Category Details - Neutrophils: Most abundant; first responders, phagocytic (bacteria). - Lymphocytes: B cells (antibodies), T cells (cell-mediated immunity), NK cells (virus/tumor). Types - Monocytes: Differentiate into macrophages and dendritic cells; phagocytic. - Eosinophils: Combat parasites, involved in allergic reactions. - Basophils: Release histamine, involved in inflammation. - Part of the immune system. General Nature - Colorless with a nucleus. - Can migrate from bloodstream to tissues. - Bone Marrow: Primary site of production. Where Produced - Lymphoid Organs: Lymphocytes mature and activate in lymph nodes, spleen, thymus. - Defense: Protect against infections. - Immune Response: Neutralize foreign substances. Functions - Inflammation: Participate in inflammatory responses. - Phagocytosis: Engulf pathogens and debris. - Antibody Production: B cells produce antibodies targeting specific antigens. ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 14 37. Platelets Characteristic Description General Nature Small cell fragments derived from megakaryocytes. Where Produced Red bone marrow. Involved in blood clotting, secrete chemicals to promote vasoconstriction and help stop Function bleeding. Blood Components in detail Component Details Plasma (55%) Water Solvent for carrying substances, absorbs heat Sodium, Potassium, Calcium, Magnesium, Chloride, Bicarbonate Salts (Electrolytes) Functions: Osmotic balance, pH buffering, membrane permeability regulation Albumin (Osmotic balance, pH buffering), Fibrinogen (Blood clotting), Globulins (Defense via antibodies, Plasma Proteins lipid transport) Substances Nutrients (glucose, fatty acids, amino acids, vitamins), Waste products (urea, uric acid), Respiratory Transported gases (O2, CO2), Hormones Formed Elements (45%) Erythrocytes Number: 4-6 million per mm³ of blood (RBCs) Function: Transport oxygen, help transport carbon dioxide Number: 4,000-11,000 per mm³ of blood Leukocytes (WBCs) Types: Basophil, Eosinophil, Neutrophil, Lymphocyte, Monocyte Function: Defense and immunity ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 15 Component Details Number: 250,000-500,000 per mm³ of blood Platelets Function: Blood clotting ANAT1052 UNIT 4 CARDIOVASCULAR SYSTEM 16