ch4.1 structure of respiratory system

• air passages

  A) nasal cavity

  B) pharynx

  C) larynx

  D) bronchioles

  E) trachea

  F) bronchi

  G) diaphragm

  H) alveoli

  
• function of respiratory system = to ensure that all cells have a constant supply of oxygen and that carbon dioxide is continually removed from the cells
• nasal cavity - air passes through the nose and is warmed and moistened before entering the lungs; contains cilia to trap dust and debris
• pharynx - from nasal cavity to top of trachea; air travels here before being diverted into the trachea by the epiglottis
• epiglottis - flap of tissue that stops food and liquid from entering the lungs
• larynx - cartilage structure joining pharynx and trachea that contains the vocal cords
• trachea (windpipe) - made of cartilage rings; carries air into and out of lungs
• bronchi - trachea splits into two primary bronchi that carries air into the lungs; made of cartilage rings
• bronchioles - small air tubes within the lungs made of smooth muscle and elastin which allows control of air flow in the lungs; contains cilia
• lungs - each lung divided into lobes (left has 2, right has 3)
• alveoli - tiny air sacs where gas exchange occurs
• pleura - membrane that lines the lungs and the chest cavity
• pleural fluid - holds the lungs against the inside of chest