Structure of Human Ventilation System 2

Structure : 

• ciliates epithelial cells
• goblet cells
• smooth muscle
• C-shaped rings of cartilage

Function : 

• main airway from mouth/nose into thorax

{goblet cells + ciliates cells- protect against infection
cartilage - prevents trachea collapsing and keep it open so air can flow}

Structure : 

• branches of trachea
• ciliates epithelial cells
• goblet cells
• smooth muscle
• cartilage

Function : 

• allow air to travel in/out of each lung

Structure : 

• branches of bronchi
• ciliate’s epithelial cells
• smooth muscle

Function : 

• allow air to travel in/out of the alveoli

Structure : 

• tiny air sacs
• walls made of a single layer of squamous epithelial cells
• elastin in walls
• surrounded by capillaries
• moist surfaces
• produce surfactant

Function : 

• site of gas exchange
• elastin allows alveoli to stretch (breath in) and recoil (breath out)

Structure : 

• muscle between ribs
• internal intercostal muscles
• external intercostal muscles

Function : 

• external intercostal muscles contract to cause inspiration
• internal intercostal muscles contract to allow forced expiration

Structure : 

• dome-shaped muscular sheet at the bottom of the thorax

Function : 

• contracts to cause inspiration
• relaxes to cause expiration

Structure : 

• serous membranes that line the lungs and inside of the body cavity

Function : 

• secrete serous fluid to reduce friction allowing the membranes to slide over each other during inspiration/expiration
• protect the lungs as they stop the lungs adhering to the body cavity wall