تشريح محاضره 1;MCQ

• The wavelength of visible light ranges from about 400 nm (violet) to approximately 750 nm (red).
• the speed of light is constant
• Conducting zone


  The respiratory passageways that carry air to the sites of gas exchange
• Respiratory zone


  The actual site of gas exchange in the lungs
• Organs of the respiratory system

  • The nose
  • Nasal cavity and paranasal sinuses
  • Pharynx
  • Larynx
  • Trachea
  • Bronchi and their smaller branches
  • Lungs

  
• The nose


  • External portion of the respiratory system, supported by bone and cartilage
  • Internal nasal cavity divided in half by midline nasal septum and lined with respiratory mucosa
  • Produces mucus, warms, filters and moistens incoming air
  • Resonance chamber for speech
  • Roof contains olfactory mucosa (receptors for sense of smell)

  
• Paranasal sinuses


  • Mucosa-lined hollow cavities within the sphenoid and ethmoid, maxillary, and frontal bones
  • Function the same as nasal cavity; and also lighten skull

  
• Pharynx


  • Passageway connecting nasal cavity to larynx and oral cavity to esophagus
  • Has three subdivisions: nasopharynx, oropharynx, and laryngopharynx
  • Passageway for air and food
  • Houses tonsils which respond to inhaled or ingested antigens

  
• Larynx


  • Connects pharynx to trachea; framework of cartilage and dense connective tissue
  • Opening (rima glottidis) can be closed by epiglottis or vocal folds
  • Functions as air passageway; prevents food from entering lower respiratory tract
  • Houses true vocal cords which are the voice production

  
• Trachea


  • Flexible tube running from larynx and dividing inferiorly into two main (primary) bronchi
  • Walls contain C-shaped cartilages that are incomplete posteriorly where trachealis muscle occurs
  • Functions as air passageway; filters, warms, and moistens incoming air

  
• piglottis or vocal folds


  Connects the larynx to the trachea

  
• Larynx


  A cartilaginous framework that houses the true vocal cords (or vocal folds) which are the sound production mechanism

  
• Larynx


  • Functions as an air passageway
  • Prevents food from entering the lower respiratory tract

  
• Trachea


  A flexible tube running from the larynx and dividing inferiorly into two main (primary) bronchi
• Trachea


  • Walls contain C-shaped cartilages that are incomplete posteriorly where the trachealis muscle occurs
  • Functions as an air passageway, filters, warms, and moistens incoming air

  
• Bronchial tree


  Consists of right and left main bronchi, which subdivide within the lungs to form lobar (secondary) and segmental (tertiary) bronchi, smaller bronchi, and bronchioles

  
• Bronchial tree


  • Bronchiolar walls contain a complete layer of smooth muscle, constriction of this muscle impedes expiration
  • Functions as air passageways connecting the trachea with the alveoli, warms and moistens incoming air

  
• Alveoli


  Microscopic chambers at the end of the bronchial tree, walled by simple squamous epithelium underlain by a thin basement membrane, their external surfaces are intimately associated with pulmonary capillaries

  
• Alveoli


  • They are the main sites of gas exchange
  • Type II alveolar cells produce surfactant which reduces surface tension and helps prevent lung collapse

  
• Lungs


  Paired composite organs located within the pleural cavities of the thorax, composed primarily of alveoli and respiratory passageways, the stroma is fibrous elastic connective tissue allowing the lungs to recoil passively during expiration

  
• The lungs house passageways smaller than the main bronchi
• Pleurae


  Serous membranes, the parietal pleura lines the thoracic cavity, the visceral pleura covers the external lung surfaces, the pleurae produce lubricating fluid and make compartments for the lungs