CIRCULATORY SYSTEM AND BLOOD

• The Circulatory System's main FUNCTION: Pumps and directs blood cells and substances carried in blood to all tissues of the body.
• The Circulatory System is for transportation of nutrients, hormones, oxygen and other needed substances in the cell
• The Circulatory System excrete and moves waste, carbon dioxide and secretory products to their disposal areas/organs
• The Circulatory System can protect the body by aiding in fighting off pathogenic microorganism by providing and/or transporting the cells and substances needed for this purpose.
• 2 Divisions of Circulatory System:

  • Cardiovascular System
  • Lymph Vascular System
• Blood Vascular System


  It is also known as Cardiovascular System
• 3 components of Cardiovascular System:

  • Heart
  • Blood Vessels
  • Blood
• 3 common basic structures of Circulatory system:

  • Tunica Intima
  • Tunica Media
  • Tunica Adventitia
• Tunica Intima


  An inner lining, comprising a single layer of extremely flattened epithelial cells called endothelial cells supported by a basement membrane and delicate collagenous tissue
• Tunica Media


  An intermediate predominantly muscular layer that contains alternating layers of smooth muscle and collagen
• Tunica Adventitia


  An outer supporting tissue layer that contains connective tissue, small vessels and nerves and vasa vasorum
• 3 Tissues of the Vascular Walls:

  • Endothelium
  • Smooth Muscle
  • Connective Tissue
• Endothelium


  Present in the internal surface (tunica intima) of all components of cardiovascular and lymphatic system and maintain a selectively permeable, antithrombogenic (inhibitory to clot formation) barrier
• Endothelium


  It determine when and where white blood cells leave the circulation for the interstitial space of tissues
• Paracrine Factors

  Endothelium secrete a variety of _ _ signals vessel dilation, constriction, and growth of adjacent cells.
• Smooth Muscle


  It occur in the walls of all vessels larger than capillaries and are arranged helically in layers and permit regulated vasoconstriction and vasodilation
• Connective tissue


  A tissue of the vascular walls that is present in the outermost layer (tunica adventitia)
• Connective Tissue


  It has two components: Collagen found in subendothelial layer and Elastic Fibers that provide resiliency to blood vessel
• Heart


  A hollow muscular organ, about a size of a clenched fist, located in the central mediastinum of thoracic cavity.
• 4


  How many chambers does the heart have?
• Heart


  A modified artery that has a pumping capacity that propels blood to the arteries of both the systemic and pulmonary circulations
• 2 Circulations of Blood in the Heart:

  • Systemic Circulation

  • Pulmonary Circulation
• Systemic Circulation


  A circulation in the heart where blood brings nutrients and removes waste in tissues throughout the body
• Pulmonary Circulation

  A blood circulatuon where the blood is oxygenated in the lungs (both left and right)
• 3 layers of the heart:

  • Endocardium

  • Myocardium

  • Epicardium
• Endocardium


  Layers of the heart that is composed of endothelium and fibroelastic tissue, smooth muscle fibers and modified cardiac muscle fibers
• Myocardium


  A contractile cardiac muscle fibers arranged spirally around each heart chamber.
• Myocardium


  It is much thicker in the walls of ventricles (particularly in the left ventricle) than atrial walls
• Epicardium


  Simple squamous mesothelium supported by a layer of loose connective tissue containing blood vessels and nerves
• Epicardium


  It corresponds to visceral layer of pericardium (the membrane surrounding the heart)
• Tunica Serosa and Visceral Pericardium

  Two other term for Epicardium
• Cardiac Skeleton

  It forms base for all cardiac valves and separates atria from ventricles & provides points of insertion for cardiac muscle in the atria and ventricle
• Cardiac Skeleton

  It helps coordinate the heartbeat by acting as electrical insulation between atria and ventricles
• Dense Irregular Connective Tissue

  Tissue composition of Cardiac Skeleton
• Cardiac Conducting System

  It is pecialized to generate and conduct waves of depolarization which stimulates rhythmic contractions and consists of modified cardiac muscle fibers
• 4 compositions of Cardiac Conducting System:

  Sinoatrial Node

  Atrioventricular Node

  Atrioventricular Bundle

  Purkinje Fibers
• Sinoatrial Node

  It is made up of cardiac muscle cells with myofibrils and some intercalated discs
• Pacemaker


  It is also known as Sinoatrial Node
• Atrioventricular Node


  It is located in the floor of the right atrium, near the AV valve and composed of cells similar with the Sinoatrial Node
• Atrioventricular Bundle

  It connects the atrial and ventricular chambers of the heart