Respiratory and Circulatory system

• Respiratory system


  Also known as the human breathing system, responsible for taking in oxygen and expelling carbon dioxide
• Parts of the respiratory system

  • Nose and mouth
  • Nasal cavity or nasal passageways
  • Pharynx
  • Larynx
  • Trachea
  • Lungs
  • Bronchi
  • Bronchioles
  • Alveoli
• Inhalation


  1. Oxygen enters the body

  2. Ribs move out, chest space increases

  3. Diaphragm muscle contracts, moves down
• Exhalation


  1. Carbon dioxide exits the body

  2. Ribs move in, chest space decreases

  3. Diaphragm muscle relaxes, moves up
• Circulatory system


  Also known as the cardiovascular system, the life support structure that nourishes cells and delivers materials in the body
• Major parts of the circulatory system

  • Heart
  • Blood vessels (arteries, veins, capillaries)
  • Blood
• The heart is a hollow muscle as big as your fist
• Parts of the heart

  • Right atrium
  • Left atrium
  • Right ventricle
  • Left ventricle
  • Tricuspid valve
  • Bicuspid valve
  • Pulmonary valve
  • Aortic valve
  • Superior vena cava
  • Inferior vena cava
  • Pulmonary artery
  • Pulmonary vein
  • Aorta
• Circulatory system function

  Air enters lungs, goes to left side of heart, pumped through body, oxygen and nutrients delivered to cells, carbon dioxide returned to right side of heart, expelled through lungs
• Types of circulation

  • Pulmonary circulation
  • Coronary circulation
  • Systemic circulation
• The circulatory system functions with other body systems to deliver different materials in the body, circulating vital elements like oxygen and nutrients while also transporting waste away
• Deoxygenated blood enters the right atrium through the superior vena cava or inferior vena cava.
• Atriums are thin-walled chambers that receive blood from veins
• Blood flows from the right side to the left side of the heart.
• The heart has four chambers - two atria and two ventricles
• The heart is located between the lungs, behind the sternum (breastbone), and to the left side of the body.
• Valves prevent backflow of blood between chambers
• Ventricles are thicker walled chambers that push out blood into arteries
• Tricuspid valve separates the right atrium from the right ventricle
• The heart's walls are made of three layers of tissue called endocardium, myocardium, and epicardium.
• The heart pumps blood into the aorta which carries oxygenated blood throughout the rest of the body.
• Bicuspid valve separates the left atrium from the left ventricle
• Myocardium makes up most of the thickness of the heart wall and contracts to pump blood through the heart.
• Coronary artery supplies blood to the heart muscle itself
• Capillaries are tiny tubes where exchange occurs between cells and blood.
• Arteries have thick muscular walls to withstand high pressure as they leave the heart.
• Capillaries are small blood vessels that connect arterioles to venules and allow for the exchange of substances between tissues and blood.