pmls

• PMLS midterm
• Lesson title: THE CIRCULATORY SYSTEM
• Legend


  • meaning, definition
  • definition
  • example
  • Name, tific
  • Name, classification
• Parts of the human heart

  • Vena Cava
  • Aorta
  • Pulmonary Artery
  • Right Atrium
  • Lept Atrium
  • Right ventricle
  • Lert verticle
• External Structure of the Heart
• B.MAIN LESSON
• The blood vessels


  • Vein
  • Arteries
  • Capillaries
• Functions


  • Pressure
  • Lumen diameter
  • Wall thickness
  • Wall layers
• Vein


  Send blood to the heart
• Arteries


  Send blood from the heart
• Vein


  • Low pressure
  • Wide lumen
  • Thin wall
  • Three layers
• Arteries


  • High pressure
  • Narrow lumen
  • Thick wall
  • Three layers
• Capillaries


  • Material exchange
  • Low pressure
  • Extremely narrow lumen
  • Extremely thin wall
  • One layer
• Veins of the antecubital fossa


  • Median cubital vein
  • Basilic vein
  • Cephalic vein
• Structures of the Heart

  • Chambers
  • Heart Valves
• Chambers


  • Two Atria - smaller chambers near the top of the heart that collect blood from the body and lungs
  • Two Ventricles - larger chambers near bottom of the heart that pump blood to body and lungs
• Heart Valves


  • Atrioventricular Valves - valves that are located between atria and ventricles that prevent backflow of blood
  • Semilunar Valves - valves located between ventricles and arteries
• Blood Vessels


  • Vena cavae (Superior and Inferior) - drains deoxygenated blood from the body to the right atrium
  • Pulmonary artery - carries deoxygenated blood pumped by the right ventricle to the lungs
  • Pulmonary vein - carries oxygen-rich blood from the lungs and received by the left atrium
  • Aorta - biggest artery; carries oxygen-rich blood pumped by the left ventricle going to the different body systems
• Pathway of Blood Through the Heart

  1. Deoxygenated blood from the body systems returns to the right atrium

  2. From the right atrium, deoxygenated blood passes through the tricuspid valve and into the right ventricle

  3. The right ventricle contracts to pump deoxygenated blood through the pulmonary semilunar valve and into the pulmonary trunk

  4. Oxygenated blood exits through the capillary network of the lungs then enters into the left and right pulmonary veins going back to the heart

  5. In the heart, it enters through the left atrium, then passes by the bicuspid or mitral valve and into the left ventricle

  6. The left ventricle contracts to force blood out through the aortic semilunar valve and into the aorta

  7. From the aorta, oxygenated blood is delivered to all areas of the body
• Cardiac Cycle


  • Atrial Systole
  • Ventricular Systole
  • Diastole
• Systole


  Contraction phase of the heart
• Diastole


  Relaxation phase of the heart
• Steps in the Cardiac Cycle

  1. The sinoatrial (SA) node, located in the upper right atrium, is the pacemaker of the heart and initiates the heartbeat

  2. The atrioventricular (AV) node located in the lower interatrial septum receives the electrical impulse and both the right and left atria contract forcing blood to the ventricles

  3. The impulse passes to the AV bundle that separates into right and left bundle branches

  4. In the right and left bundle branches the impulse travels to the Purkinje fibers covering the ventricles, causing them to contract, forcing blood into the aorta and pulmonary artery

  5. The cycle starts again
• Heart Rate, Pulse Rate and Blood Pressure


  • Heart rate - number of times the heart beats per minute
  • Pulse rate - number of times the arteries create a noticeable pulse as a result of heart contraction
  • Blood Pressure - force of blood moving through the blood vessels
• Blood


  The body's main fluid for transporting nutrients, waste products, gases, and hormones through the circulatory system
• Blood


  • Normal volume: 5-6 liters
  • Consists of 2 parts: (1) Plasma, the liquid portion and; (2) Formed elements, the cellular portion
• Plasma


  Comprises 55% of the total blood volume; it is a clear, straw-colored fluid that is 91% water and 9% dissolved substances; It is the transporting medium for plasma proteins, nutrients, minerals, gases, vitamins, hormones, and blood cells, as well as waste products of metabolism
• Formed elements


  Constitute approximately 45% and includes the Erythrocytes, Leukocytes, and Thrombocytes
• Types of Blood Cells

  • Erythrocytes (Red Blood Cells)
  • Leukocytes (White Blood Cells)
  • Thrombocytes (Platelets)
• Erythrocytes (Red Blood Cells)

  • Biconcave disks
  • 7.2 microns in diameter
  • Contain hemoglobin to transport Oxygen and Carbon Dioxide
  • Life spans is 120±20 days
• Leukocytes (White Blood Cells)


  • Provide immunity to certain diseases by producing antibodies and destroying harmful pathogens by phagocytosis
  • Divided into Granulocytes and Agranulocytes
• Granulocytes


  • Neutrophils
  • Eosinophils
  • Basophils
• Neutrophils


  • Nucleus is 2 to 5 lobes and cytoplasm has very fine granules
  • 10-12 micrometers in diameter
  • Helps in the destruction of bacteria
  • 1st phagocytic cell to respond against antigens
  • Lifespan in the blood stream is 8 hours and produced everyday in the bone marrow
  • Predominant cells in pus
• Eosinophils


  • Responsible for combating infections in parasites of vertebrates and for controlling mechanisms associated with the allergy and asthma
  • The granules in cytoplasm of eosinophils stain red-orange, and the nucleus has only two lobes
• Basophils


  • Least common WBC
  • Cytoplasm contains large granules that stain purple-black
  • Release histamine in the inflammation process and heparin to prevent abnormal blood clotting
• Agranulocytes


  • Lymphocytes
  • Monocytes
• Lymphocytes


  • Second most numerous leukocytes
  • Has a large round purple nucleus with a rim of sky-blue cytoplasm
  • Increases in viral infection
  • Has three types: B-cells, T-cells, and Natural Killer cells
• Monocytes


  • Largest circulating leukocytes
  • Powerful phagocytes to digest foreign material
  • Cytoplasm has a fine blue-gray appearance with vacuoles and a large, irregular nucleus
  • A tissue monocyte is known as "macrophage"
  • Increases in intracellular infections and tuberculosis
• Thrombocytes (Platelets)


  • Small, irregularly shaped disks formed from the cytoplasm of very large cells in the bone marrow called the megakaryocytes
  • Life span is 9 to 12 days
  • Play a vital role in blood clotting in all stages of the coagulation mechanism (hemostasis)
• Composition of Blood