Respiratory Sytstem

• General Functions:

  1. Pulmonary Ventilation
  2. External Respiration
  3. Transport of Gases
  4. Internal Respiration
• Pulmonary Ventilation

  • called breathing
  • process of moving air into out to our lungs
• External Repsiration

  • oxygen from lungs to blood
  • occurs between the alveoli and the pulmonary capillaries
  • CO2 from blood to air spaces in the lungs
• Transport of Gases

  • movement of oxygen from the lungs to the body tissues
  • CO2 move from the body to the lungs, vice versa
• Internal Respiration

  • oxygen will move from the blood to the body tissues
  • CO2 will move/diffuse from the body tissues to the blood
• Diffusion is a passive movement, from high concentration to a lower concentration area
• Human Respiratory System has two major functional zones:

  1. Conducting Zone
  2. Respiratory Zone
• Conducting Zone

  • serves as the passageway of air into the kungs
• Respiratory Zone

  • consists of structures that facilitate gas exchanges
• Nose helps moisten, warm, and filter the incoming air

  • primary entrance of air to the respiratory tract.
• Nasal Cavity

  • consists of nasal hair (vibrissae) and cilia, both of which filter the air
• Nasal cavity have microscopic strands that filter bacteria cells and mucus
• Vibrissae is located at the outer portion of nasal cavity
• Cilia is in the inner portion of nasal cavity and are microscopic
• Pharynx: the membrane-lined cavity behind the nose and mouth, connecting them to the esophagus.
• Pharynx

  • throat serves as a passageway for both air and food into the esophagus
• The mucus membrane helps moisten the air that comes inside the body due to mucus

  • mucus can also help trap particles from the air.
• Epiglottis

  • cartilaginous structure helps close the entrance to the trachea when swallowing food
• Larynx

  • also termed voice box
  • helps in sound production and also protects the trachea from food aspiration
• Upper Respiratory Tract

  1. Nose
  2. Nasal Cavity
  3. Pharynx
  4. Epiglottis
  5. Larynx
• Lower Respiratory Tract: Trachea Bronchi Bronchioles Alveoli
• Trachea

  • consists of cilia that propel debris- containing mucus back into the esophagus
  • windpipe connects the larynx and pharynx to the lungs.
  • runs down from the neck until it splits into two bronchi
• Bronchi (plural)

  • two branches connect our trachea and our lungs
  • originate from the trachea that penetrate i to each of the lungs
  • branch up to around 23 times to form the smaller bronchioles
• Right lung is bigger than the left
• General Mechanism of breathing

  1. referred as the pulmonary ventilation
  2. mechanical movement of air intro and out to the lungs
• Air In Stage

  1. Respiratory muscle contraction
  2. Increase in the volume of the lungs
  3. Decrease in the air pressure in lungs
• Air Out

  1. Respiratory muscle relaxation
  2. Decrease in the volume of the lungs
  3. Increase in the air pressure in the lungs
• Alveolar Gas Exchange

  • external respiration or pulmonary gas exchange
  • The diffusion of gases in the lungs is possible due to the difference in the concentration or partial pressures of oxygen or carbon dioxide between the alveoli and the blood within the capillaries.
• Alveolus: has a higher concentration of O2; in blood, lower
• In CO2 partial pressure:

  Alveolus: Lower

  Blood: Higher
• Cigarette smoking can affect gas exchange within the respiratory

  tract by causing lung diseases that damage the airways and the

  alveoli in the lungs.
• Inhalation decreases the air pressure within the lungs. The resulting

  difference in air pressure between the lungs and the atmosphere causes air

  to rush into the lungs.
• Exhalation increases in air pressure in the lungs. The higher pressure in the

  lungs compared to that in the atmosphere pushes air out of the lungs.
• Breathing action is possible due to the action of the respiratory muscles and ribcage.
• Nostrils

  • openings that serve as the primary entry point for air into the inner respiratory tract
• pharynx is a tube that connects the oral cavity and nasal cavity to the esophagus. Thus, this part of the conducting zone is a passageway for both food and air.
• epiglottis is a cartilaginous flap of tissue that closes the opening to the trachea when swallowing food. It prevents food from entering the lower respiratory tract.
• The larynx protects the trachea from food aspiration and has cartilage tissues that facilitate sound production
• trachea or windpipe is a part of the lower respiratory tract that connects the larynx and pharynx to the lungs
• bronchus is one of the two branches formed from the trachea. They further branch into smaller bronchioles that lead to the respiratory membrane of the lungs