Respiratory System

• Respiratory System


  Responsible for breathing wherein gasses are exchanged to be carried by the blood for use in biological processes
• Upper respiratory tract organs

  • Nose
  • Nasal cavity
  • Nasal conchae
  • Frontal sinus
  • Sphenoid sinus
  • Pharynx
  • Larynx
• Nose


  Area where the oxygen enters the body, It enters the body through the nostrils and passes through the nasal cavity
• Nasal cavity


  Large air-filled space that extends from the nostrils to the back of the throat (pharynx)
• Nasal conchae


  • Mucosa covered projections located on the lateral wall of the nasal cavity
  • Serve to filter, heat, and moisten the air to increase the surface area to provide warming and humidification of air as it passes
• Frontal sinus


  • Located in the frontal bone just above the eyebrows
  • Lined with a mucous membrane that produces mucus, which helps moisten the nasal cavity and trap dust, bacteria, and other particles from the air we breathe
• Sphenoid sinus


  • Most profound of the cranial sinuses
  • Facilitates air circulation
  • Drains fluid via its openings
• Pharynx


  Serves both respiratory and digestive systems by receiving air and substances from the nasal and oral cavities
• Larynx


  • Also known as the voice box
  • Located at the top of the trachea
  • Acts as a passage for air to move in and out of the lungs
• Lower respiratory tract organs

  • Lungs
  • Right Lung
  • Left Lung
  • Alveoli
  • Bronchioles
  • Bronchus
  • Trachea
  • Diaphragm
• Lungs


  • Largest organs of the respiratory tract
  • Function is to inhale oxygen and exhale carbon dioxide
• Right Lung


  • Wide and short
  • Heavier and larger since it contains three lobes
• Left Lung


  • Smaller and narrow and long
  • Contains only two lobes
  • Smaller left lung allows room for the heart since the heart tilts to the left, the left lung has an indentation called the cardiac impression to accommodate the heart
• Alveoli


  • Tiny air sacs in the lungs
  • Vital for gas exchange
• Bronchioles


  Deliver air to 480 million alveoli, facilitating oxygen intake and carbon dioxide release during breathing
• Bronchus


  Main airways that branch off from the trachea (windpipe) into the lungs
• Trachea


  Allows air to enter and exit the lungs and divides into the left and right mainstem bronchi after originating from the larynx
• Diaphragm


  • Dome-shaped muscle beneath the lungs, separates the chest from the abdomen
  • Plays a vital role in breathing by contracting during inhalation and relaxing during exhalation, thus aiding in the expansion and compression of the lungs
• How the Respiratory System works.

  1. Inhale: Diaphragm contracts and moves downward, chest cavity expands, air moves in through nose/mouth, down trachea into lungs

  2. Gas exchange occurs

  3. Exhale: Diaphragm relaxes, lungs recoil, air moves out of lungs