Respiratory system

• Respiratory System


  The system responsible for breathing and gas exchange in the body
• Respiratory System

  • Air passes through the nose or mouth
  • Then into the trachea
  • The trachea splits into two tubes called bronchi
  • The bronchi split into progressively smaller tubes called bronchioles
  • The bronchioles finally end at small sacs called alveoli where gas exchange occurs
• Breathing

  1. Diaphragm and external intercostal muscles contract to move the chest cavity down and draw air into the lungs

  2. Diaphragm and internal intercostal muscles relax to move the chest cavity up and force air out of the lungs
• Oxygen and Carbon Dioxide Exchange

  • Oxygen moves from the alveoli into the blood in the surrounding capillaries
  • Carbon dioxide moves from the blood in the capillaries into the alveoli
• Alveoli have a large surface area and thin walls to facilitate efficient gas exchange
• Diffusion

  The process by which gases move from an area of high concentration to an area of low concentration
• High concentration of O2 in alveoli

  Low concentration of O2 in capillary blood
• Low concentration of CO2 in alveoli

  High concentration of CO2 in capillary blood
• Deoxygenated blood becomes oxygenated as it passes through the alveoli and exchanges gases with the air
• Aerobic Respiration


  The process of releasing energy from glucose using oxygen
• Anaerobic Respiration


  The process of releasing energy from glucose without using oxygen, producing lactic acid
• Aerobic exercise is exercise where the body can keep up with the oxygen demand of the cells
• Anaerobic exercise is exercise where the body cannot keep up with the oxygen demand of the cells
• Breathing Rate


  The number of breaths taken per minute
• Tidal Volume


  The volume of air breathed in or out during one breath
• Minute Ventilation


  The volume of air breathed in or out each minute
• A 100-metre sprint would be anaerobic exercise because the body cannot keep up with the oxygen demand of the muscles during the short, high-intensity exercise