M2. Cardiovascular system

• 2 major components of the Circulatory system?

  Cardiovascular and Lymphatic system
• The Heart is a hollow, muscular organ which is considered as the major structure of the circulatory system.
• Location of heart?

  center of the thoracic cavity between the lungs with the apex pointing down and to the left of the body
• • PERICARDIUM - thin fluid sack that surrounds the heart
• The epicardium is the thin outer layer and the protective layer that attaches to the pericardium
• MYOCARDIUM

  • Middle muscle layer
  • Contracts to pump blood into the arteries
  • Thick layer of cardiac muscles
• ENDOCARDIUM

  • Thin inner layer
  • Lines the interior chambers and valves
• ATRIA

  • Upper chambers
  • “Receiving” chambers
• VENTRICLES

  • Lower chambers
  • “Pumping” or “delivering” chambers
• RIGHT ATRIUM

  Receives deoxygenated blood from the body, through the superior and inferior vena cava, and pumps it into the right ventricle
• Pumps the deoxygenated blood received from the right atrium into the lungs?

  Right ventricle
• Receives oxygenated blood from the lungs throughout the pulmonary veins and pumps it into the left ventricle?

  Left atrium
• Pumps the oxygenated blood back to the bodily tissues through the aorta?

  Left ventricle
• The walls of the left ventricles are about 3 times thicker than the other ventricle due to the force required to pump blood into the arterial system 
• Separates the right and left atria?

  Interatrial septum
• Separates the right and left ventricles?

  Interventricular septum
• when the ventricles contracts the atrioventricular valves closes
• when the ventricles relaxes the semilunar valves closes
• • Valves at the entrance to the ventricles?

  Atrioventricular valves
• • Valves that exit the ventricles?

  Semilunar valves
• what do the valves prevent?

  Backflow
• TRICUSPID

  • Between the right atrium and right ventricle
  • Prevent blood from flowing back into the right atrium
• BICUSPID or MITRAL

  • Between the left atrium and left ventricle
  • Prevent blood from flowing back into the left atrium
• RIGHT SEMILUNAR VALVE

  • At the entrance to the pulmonary artery
  • Prevent blood from flowing back into the right ventricle
• LEFT SEMILUNAR VALVE

  • At the entrance to the aorta
  • Prevent blood from flowing back into the left ventricle
• VASCULAR SYSTEM

  • It is the system of blood vessels that, along with the heart, forms the closed loop through which blood is circulated to all parts of the body
• PULMONARY CIRCULATION

  • It carries blood from the right ventricle of the heart to the lungs to remove carbon dioxide and pick up oxygen
  • System of blood vessels responsible for carrying the deoxygenated blood from the right ventricle to the lungs for the exchange of gases
• SYSTEMIC CIRCULATION

  • It carries oxygenated blood and nutrients from the left ventricle to the body cells
  • It then returns to the right atrium of the heart with blood carrying carbon dioxide and other waste products from the cells
• ARTERIES

  • They carry oxygenated blood away from the hear
• • Arterioles: smallest branches of arteries that join with the capillaries
• • Aorta: largest artery in the body
• VEINS

  • They carry deoxygenated blood to the heart
  • Have thinner walls because the blood is under less pressure, and have the tendency to collapse more easily
• • Venules: smallest veins at the junction of the capillaries
• • Vena cava: largest vein in the body
• • Great saphenous: longest vein in the body located in the leg
• color of arterial blood?

  Bright red
• color of venous blood?

  Dark red
• • Oxygenated = from the lungs, commonly found in arteries
• Deoxygenated = returning back to the heart or lungs, commonly found in veins
• • Microscopic, one-cell-thick vessels?

  Capillaries