respiratory system t4

• What are the two main structural divisions of the respiratory system?


  Upper respiratory system and lower respiratory system
• What is the function of the conducting zone in the respiratory system?


  It conducts air to the lungs
• Which structures are included in the conducting zone?


  Nose, pharynx, larynx, trachea, bronchi, bronchioles, and terminal bronchioles
• What is the main site of gas exchange in the respiratory system?

  Respiratory zone
• What structures are part of the respiratory zone?


  Respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli
• What is the external nose?


  The portion visible on the face
• What is the internal nose?


  A large cavity beyond the nasal vestibule
• What are the internal nares or choanae?


  They are openings in the internal nose
• What ducts open into the internal nose?

  Ducts from paranasal sinuses and nasolacrimal ducts
• How is the nasal cavity divided?


  By the nasal septum
• What is the function of the nasal conchae?


  They subdivide the cavity into meatuses, increasing surface area and preventing dehydration
• Where are olfactory receptors located?


  In the olfactory epithelium
• What is the pharynx and where does it start and end?


  It starts at the internal nares and extends to the cricoid cartilage of the larynx
• What are the functions of the pharynx?


  Passageway for air and food, resonating chamber, and houses tonsils
• What are the three anatomical regions of the pharynx?


  Nasopharynx, oropharynx, and laryngopharynx
• What is the larynx and what does it connect?


  A short passageway connecting the laryngopharynx with the trachea
• How many pieces of cartilage compose the larynx?


  9 pieces of cartilage
• What is the thyroid cartilage also known as?


  Adam's apple
• What is the cricoid cartilage known for?


  It is a hallmark for tracheotomy
• What does the epiglottis do during swallowing?


  It closes off the glottis
• What is the glottis?

  A pair of folds of mucous membranes
• What are the two types of vocal folds?


  Ventricular folds (false vocal cords) and vocal folds (true vocal cords)
• What is the function of the ventricular folds?


  They hold breath against pressure in the thoracic cavity
• How do vocal folds produce sound?


  Muscle contraction pulls elastic ligaments which stretch vocal folds into the airway
• What factors can change the sound produced by vocal folds?


  They can move apart or together, elongate or shorten, and be tighter or looser
• How do androgens affect vocal folds?


  They make folds thicker and longer, resulting in slower vibration and lower pitch
• What does the trachea divide into?


  Right and left primary bronchi
• What are the four layers of the trachea?


  Mucosa, submucosa, hyaline cartilage, and adventitia
• How many C-shaped rings of hyaline cartilage are in the trachea?


  16-20 C-shaped rings
• What is the carina in the bronchi?


  An internal ridge that triggers the cough reflex
• How does branching affect the mucous membrane in the bronchi?


  It changes as the bronchi branch
• What happens to cartilage and smooth muscle as bronchi branch?


  As cartilage decreases, smooth muscle increases
• What is the role of the sympathetic ANS in the bronchi?


  It causes relaxation and dilation
• What is the role of the parasympathetic ANS in the bronchi?


  It causes contraction and constriction
• How are the lungs separated?

  By the heart and other structures in the mediastinum
• What encloses each lung?

  A double-layered pleural membrane
• What are the two layers of the pleural membrane?

  Parietal pleura and visceral pleura
• What is the pleural cavity?


  The space between the layers of pleura
• What is the function of pleural fluid?


  It reduces friction and produces surface tension
• What is the cardiac notch?


  A feature that makes the left lung 10% smaller than the right lung