Respiratory system

• what is respiration? + three major parts

  sequence of events resulting in the exchange of oxygen and carbon dioxide. the airway, the lungs, and the muscles of ventilation
• major organs of the respiratory system

  nose, trachea, bronchioles, mouth, lungs, pharynx and larynx, bronchi, alveoli
• muscles of respiration include

  the diaphragm and intercostal muscles - work together during inspiration and expiration (breathing in/out)
• Respiratory system

  
• nose/nasal cavity

  comprised of cartilage, bone, and skin. contains epithelial tissue and secretes mucous. the function is to warm, humidity, and filter air entering the body before it reaches the lungs. Cilia lining the nasal cavity trap particles such as dust and act as 1st line of defense against foreign microorganisms. First section of airway
• mouth/oral cavity

  secondary external opening, foreign materials can potentially enter the respiratory system. Advantages - shorter distance/larger opening allowing more air to enter the airway.
• The nose and mouth

  
• the pharynx

  works with both the respiratory and digestive systems. receives air from the nasal cavity, receives food from the oral cavity and used to help swallow food and water
• the pharynx is the passageway for food and air from the mouth to the esophagus.

  
• the larynx 


  directs air and food into the proper channels. comprised of eight pieces of cartilage. plays a vital role in human speech
• the trachea


  the first structure of the lower respiratory tract - "windpipe". the only pathway to the lungs and functions to provide a passageway for air to be inhaled and exhaled. made up of flexible soft cartilage connected by dense connective tissue to protect it from collapsing.
• the larynx and trachea

  
• the lungs

  main function - perform the exchange of oxygen and carbon dioxide. major organ of the respiratory system. soft, spongy structures, made up of elastic connective tissue. contains two lobes. located within the thoracic cavity
• differences between external and internal respiration

  External - oxygen diffuses from alveolar air into blood, carbon dioxide diffuses out from the blood into the alveolar air. Internal - oxygen diffuses out from blood to tissues, carbon dioxide diffuses into blood from the tissue
• Pulmonary ventaliation

  movement of air through the passageways between the external environment and the lungs
• Disorders of the respiratory system

  Asthma Bronchitis Pheumonia