Respiratory System

• Respiratory system


  The system that brings oxygen into the body and removes carbon dioxide
• Breathing


  1. Brings oxygen in the air into the lungs

  2. Moves oxygen through the body

  3. Removes carbon dioxide from the blood and releases it into the air
• Lungs


  • Remove oxygen from the air and pass it through the bloodstream
  • Take carbon dioxide from the blood and release it into the air
• Sinuses


  Hollow spaces in the bones of the head that help regulate the temperature and humidity of air, lighten the bone structure, and give tone to the voice
• Nasal cavity (nose)


  The best entrance for outside air into the respiratory system, with hairs that are part of the air-cleansing system
• Oral cavity (mouth)

  Can also be an entrance for air, especially if nasal passages are blocked
• Adenoids


  Overgrown lymph tissue at the top of the throat that can interfere with breathing and are sometimes removed
• Lymph system


  Carries fluid throughout the body, helps resist infection by filtering out foreign matter and producing cells to fight them
• Tonsils


  Lymph nodes in the wall of the pharynx that are not an important part of the germ-fighting system and are sometimes removed if infected
• Pharynx (throat)


  Collects incoming air from the nose and passes it downward to the trachea
• Epiglottis


  A flap of tissue that guards the entrance to the trachea and closes when anything is swallowed that should go into the esophagus and stomach
• Larynx (voice box)


  Contains the vocal cords that create voice sounds when moving air is breathed in and out
• Esophagus


  The passage leading from the mouth and throat to the stomach
• Trachea (windpipe)


  The passage leading from the pharynx to the lungs
• Ribs


  Bones supporting and protecting the chest cavity, moving slightly to help the lungs expand and contract
• Bronchi


  The two main tubes that the trachea divides into, one for each lung, which then subdivide further into bronchioles
• Right lung


  Divided into three lobes or sections
• Left lung


  Divided into two lobes
• Pleura


  The two membranes that surround each lobe of the lungs and separate the lungs from the chest wall
• Cilia


  Hair-like structures that line the bronchial tubes and have a wave-like motion to carry mucus upward and out
• Mucus


  Sticky phlegm or liquid that catches and holds dust, germs, and other unwanted matter that has invaded the lungs, and is coughed up or swallowed
• Diaphragm


  The strong wall of muscle that separates the chest cavity from the abdominal cavity, moving downward to create suction and expand the lungs
• Bronchioles


  The smallest section of the bronchi, at the end of which are the alveoli
• Alveoli


  The very small air sacs that are the destination of the air that is breathed in
• Capillaries

  Blood vessels imbedded in the walls of the alveoli, where blood passes through to move carbon dioxide into the alveoli and take up oxygen
• Pulmonary artery


  Brings blood to the capillaries in the alveoli
• Pulmonary vein

  Takes blood away from the capillaries in the alveoli
• Respiratory system


  System that supplies every cell in the body with oxygen and removes carbon dioxide
• Oxygen is needed for cellular respiration, which generates the energy we use to think and move around
• Without oxygen, we can't produce energy and we don't last very long
• Respiratory system


  • Supplies oxygen to the body
  • Removes carbon dioxide from the body
• Pulmonary ventilation (breathing)


  1. Air enters the lungs from the surroundings

  2. Oxygen gets from the lungs to the blood

  3. Carbon dioxide gets from the blood to the lungs
• Components of the respiratory system

  • Nose
  • Nasal cavity
  • Paranasal sinuses
  • Larynx
  • Trachea
  • Bronchi
  • Lungs (containing alveoli)
• Respiratory zone


  Where gas exchange occurs within the lungs
• Conducting zone


  All the other components where air comes in and out of the body
• Nasal cavity


  • Filters, heats, and moistens the air
  • Surrounded by paranasal sinuses that produce mucus
• Pharynx


  • Connects the nasal cavity with the mouth
  • Has three regions: nasopharynx, oropharynx, and laryngopharynx
• Larynx


  • Provides an airway
  • Site of voice production
  • Contains cartilages like the epiglottis that stay open for airflow but cover the laryngeal inlet when swallowing
• Trachea and bronchi


  1. Trachea descends and divides into two main bronchi

  2. Bronchi subdivide into lobar, segmental, and terminal bronchioles
• Bronchioles


  • Epithelium gets thinner
  • Less cartilage
  • More smooth muscle