Respiratory system

• Human Respiration


  The human respiratory system allows one to obtain oxygen, eliminate carbon dioxide
• Phases of Breathing


  • Inspiration (inhalation)
  • Expiration (exhalation)
• Inspiration


  The process of taking in air
• Expiration


  The process of blowing out air
• Functions of the Respiratory System

  • Provides for exchange of oxygen and carbon dioxide to and from the blood
  • Pulmonary ventilation - air moves in and out of lungs, continuous replacement of gases in alveoli
  • External respiration - gas exchange between blood and air at alveoli
  • Transport of respiratory gases between the lungs and the cells of the body
  • Internal respiration - gas exchange in capillaries between blood and tissue cells
• Pulmonary Ventilation


  Air moves in and out of lungs, continuous replacement of gases in alveoli
• External Respiration


  Gas exchange between blood and air at alveoli, O2 in air diffuses into blood, CO2 in blood diffuses into air
• Transport of Respiratory Gases


  Between the lungs and the cells of the body, performed by the cardiovascular system, blood is the transporting fluid
• Internal Respiration


  Gas exchange in capillaries between blood and tissue cells, O2 in blood diffuses into tissues, CO2 waste in tissues diffuses into blood
• Organs in the Respiratory System

  • Nose/nasal cavity
  • Pharynx (throat)
  • Larynx
  • Trachea (windpipe)
  • Bronchi
  • Bronchioles
  • Alveoli
• Upper Respiratory Tract


  Nasal cavities, pharynx - the section that takes air in and lets it out
• Lower Respiratory Tract


  Larynx, trachea and lungs (alveoli and branchial tube)
• Components of the Respiratory System

  • Conducting Portion - cleans and humidifies the inspired air and provides a conduit through which air moves to and from the lungs
  • Respiratory Portion - main function of gas exchange
• Conducting Portion


  Nasal cavities, nasopharynx, larynx, trachea, bronchi, bronchioles, terminal brochioles
• Respiratory Portion


  Respiratory bronchioles, alveolar ducts, alveoli - cellular sites of the exchange of oxygen and carbon dioxide, saclike structure that make up most of the lungs
• Nasal Cavities


  • Vestibules create turbulence in inspired air
  • Nares (nostrils) have sweat glands and coarse moist vibrissae that filter some material from inspired air
  • Respiratory epithelium covers the middle and inferior conchae
  • Olfactory epithelium for sense of smell is located on the superior conchae at the roof of the nasal cavity
• Types of Respiratory Epithelium

  • Ciliated columnar cells (most abundant)
  • Goblet cells (secrete mucus)
  • Brush cells (chemosensory receptors)
  • Small granule cells (part of diffuse neuroendocrine system)
  • Basal cells (mitotically active stem and progenitor cells)
• Olfactory Epithelium


  Pseudostratified columnar epithelium with olfactory neurons, supporting cells, and basal cells (stem cells)
• Pleura


  Flattened sac of serous membrane around each lung, pleural cavity is a slit-like potential space filled with pleural fluid
• Ventilation


  Breathing, pulmonary ventilation - mechanical forces cause the movement of air, gases always flow from higher pressure to lower
• Muscles of Inspiration


  • Diaphragm flattens as it contracts, increasing the height of the thoracic cavity
  • External intercostal muscles contract to raise the ribs, increasing the circumference of the thoracic cavity
• Peripheral Chemoreceptors Regulating Respiration


  Aortic bodies and carotid bodies send sensory information to the medulla
• Components of the Upper Respiratory Tract


  • Nasal cavities, pharynx, larynx
• Functions of the Upper Respiratory Tract

  • Passageway for respiration
  • Receptors for smell
  • Filters incoming air
  • Moistens and warms incoming air
  • Resonating chambers for voice
• Components of the Lower Respiratory Tract


  • Larynx, trachea, bronchi, lungs
• Functions of the Lower Respiratory Tract

  • Larynx maintains open airway, routes food and air, assists in sound production
  • Trachea transports air to and from lungs
  • Bronchi branch into lungs
  • Lungs transport air to alveoli for gas exchange
• Malfunctions & Diseases of the Respiratory System

  • Asthma - severe allergic reaction characterized by constriction of bronchioles
  • Bronchitis - inflammation of the lining of the bronchioles
  • Emphysema - condition in which the alveoli deteriorate, causing the lungs to lose their elasticity
  • Pneumonia - condition in which the alveoli become filled with fluid, preventing the exchange of gases
  • Lung cancer - irregular & uncontrolled growth of tumors in the lung tissue
• Four Respiration Processes


  • Breathing (ventilation) - air in to and out of lungs
  • External respiration - gas exchange between air and blood
  • Internal respiration - gas exchange between blood and tissues
  • Cellular respiration - oxygen use to produce ATP, carbon dioxide as waste
• The right lung has three lobes, and the left lung only has two
• The right lung is a little larger than the left lung
• A person sleeping almost always breathes twelve or fifteen times a minute
• The exhaling rate is faster in kids than in adults
• The trachea is made out of cartilage shaped rings
• The fastest recorded "sneeze speed" is 165 km per hour
• It is healthier to breathe through your nose than your mouth, because your nose hairs and mucus clean the air
• Human Respiration


  The human respiratory system allows one to obtain oxygen, eliminate carbon dioxide

  
• Breathing


  1. Inspiration (the process of taking in air)

  2. Expiration (the process of blowing out air)
• Organs in the Respiratory System

  • Nose/nasal cavity (warms, moistens, & filters air as it is inhaled)
  • Pharynx (throat, passageway for air, leads to trachea)
  • Larynx (the voice box, where vocal cords are located)
  • Trachea (windpipe, keeps the windpipe "open", lined with cilia to filter air)
  • Bronchi (two branches at the end of the trachea, each lead to a lung)
  • Bronchioles (a network of smaller branches leading from the bronchi into the lung tissue & ultimately to air sacs)
  • Alveoli (the functional respiratory units in the lung where gases are exchanged)

  
• Two divisions of the respiratory system

  • Upper respiratory tract (nasal cavities, pharynx, the section that takes air in and lets it out)
  • Lower respiratory tract (larynx, trachea and lungs (alveoli and branchial tube))

  
• Two components of the respiratory system

  • Conducting portion (cleans and humidifies the inspired air and provides a conduit through which air moves to and from the lungs)
  • Respiratory portion (main function of gas exchange)