gen biology 11

• Circulatory System


  Cardiovascular System is to provide oxygen, nutrients and hormones to muscles, tissues and organs throughout your body
• Heart


  • It pumps the blood throughout the body
  • Main organ that pumps blood to the body through a network of arteries and veins (blood vessels)
• Blood Vessels


  • Work with your heart and lungs to continuously circulate blood through your body
  • Carry the blood throughout the body
• Types of Blood Vessels


  • Veins - Carry blood towards the heart
  • Arteries - Carry blood away from the heart
  • Smallest blood vessel in the body
• Arteries


  Muscular tubes that carry oxygenated blood away from the heart and to every part of your body
• Veins


  • These blood vessels return oxygen-depleted blood to the heart
  • Veins start small (venules) and get larger as they approach your heart
• Superior vena cava


  Carries blood from the upper body (head and arms) to the heart
• Inferior vena cava


  Brings blood up from the lower body (stomach, pelvis and legs) to the heart
• Valve


  • The valves prevent blood from flowing backward
  • Veins in the legs have valves to keep blood from flowing backward
  • The heart has four valves
• The heart has four valves

  • Tricuspid valve - Located between the right atrium and the right ventricle
  • Pulmonary valve - Located between the right ventricle and the pulmonary artery
  • Mitral valve - Located between the left atrium and the left ventricle
  • Aortic valve - Located between the left ventricle and the aorta
• Capillaries


  • These blood vessels connect very small arteries (arterioles) and veins (venules)
  • Capillaries have thin walls that allow oxygen, carbon dioxide, nutrients and waste products to pass into and out of cells
• Blood


  • Made up of red and white blood cells, plasma and platelets
  • It carries material throughout the body
• Four chambers of the heart

  • Two atria - The receiving chambers of the heart, accepting blood from the body and from the lung
  • Two ventricles - The pumping chambers, moving blood to the lungs and into the body
• Circulatory system circuits


  • Pulmonary circuit - Carries blood without oxygen from the heart to the lungs, pulmonary veins return oxygenated blood to the heart
  • Systemic circuit - Blood with oxygen, nutrients and hormones travels from the heart to the rest of the body, in the veins the blood picks up waste products
  • Coronary circuit - Coronary refers to your heart's arteries, this circuit provides the heart muscle with oxygenated blood, it returns oxygen-poor blood to the heart's right upper chamber (atrium) to send to the lungs for oxygen
• Conditions and Disorders


  • Aneurysms - Occur when an artery wall weakens and enlarges, can affect any artery but aortic aneurysms, abdominal aortic aneurysms and brain aneurysms are the most common
  • High blood pressure - When the pressure (force of blood against the blood vessel walls) gets too high, puts you at risk for cardiovascular disease, heart attacks and strokes
  • Plaque deposits - High cholesterol and diabetes can lead to fat and other substances collecting in the blood, forming deposits called plaques on artery walls, this is atherosclerosis which increases the risk of blood clots, strokes, coronary artery disease, peripheral artery disease and kidney disease
• The heart is a hollow muscle, which is big as your FIST