CHAPTER 23

THE RESPIRATORY SYSTEM

 

•        Identify and state the function and location of the following:

nose

          external naris (plural = nares)

          nasal cavity

                   nasal septum (function will not be on exam)

                   nasal conchae

          internal naris

pharynx

          nasopharynx

          oropharynx

          laryngopharynx

larynx

          thyroid cartilage

          cricoid cartilage

          epiglottis

          vocal folds (vocal cords)

                   glottis (see open vs. closed in lab photos)

trachea

          cartilage rings

primary bronchus (plural = bronchi)

          secondary (lobar) bronchus

                   tertiary bronchus

                             bronchiole

                                      alveolus (plural = alveoli)

lungs

          lobes (recognize number on each side)

          cardiac notch

          visceral pleura

          parietal pleura

diaphragm

external intercostal muscles

 

·                   List in correct sequence the structures through which air outside the body travels to arrive at the alveoli.

·                   State the function of the respiratory system. Describe the four respiration events. Differentiate between internal respiration and cellular respiration (see text footnote).

·                   State the function of the respiratory mucosa's mucus, lysozyme, and cilia.

·                   Explain how the larynx directs the flow of air and food into their proper channels (You should also study figure 24.13 to understand the epiglottis mechanism). State the function of the cough reflex. Describe how sound is produced by the vocal folds. Define laryngitis. Describe the Valsalva maneuver.

·                   Know the following about the trachea. The tracheal mucosa (see figure 23.6), functionally named the MUCOCILIARY ESCALATOR, contains cilia and numerous mucus producing goblet cells. Dust and other debris, brought into the respiratory tract in the air we breathe, is trapped on the mucus. Cilia then move the mucus to the pharynx, where it is swallowed. Reason how the mucociliary escalator is affected by smoking.

·                   Explain the function of the C-shaped portion, and also the open parts of the tracheal cartilage rings.

·                   Define the Heimlich maneuver.

·                   Know that each lobe of the lung has its own airway tube and its own blood supply. Therefore a lobe can be surgically removed without stopping the function of the other lobes. Also know that secondary bronchi are called lobar bronchi because each secondary bronchus supplies air to an individual "lobe" of the lung.

·                   Know that the alveoli function as the major site of gas exchange because they are the only airway structures thin enough and with enough surface area to allow sufficient gas diffusion to sustain life. Describe the structure of the respiratory membrane and relate this structure to its function. State the function of alveolar macrophages.

·                   State the production site and function of pleural fluid.

·                   State the common name for pulmonary ventilation. Define inspiration and expiration. Describe the pressure relationships in the thoracic cavity during breathing. Describe the forces involved in the interaction between the lungs and the thorax wall. Describe atelectasis, pneumothorax and the relationship between them.

·                   Explain how changes in the volume occupied by a gas result in changes in the pressure of that gas. Explain how inspiration and expiration occur during quiet and deep (forced) ventilation. Your explanation should include muscle action, volume changes in the thorax, lung recoil due to its elasticity, and resultant pressure changes. Refer to pages 322 - 323 for a helpful description of the intercostal muscles' anatomy and involvement in ventilation. You will not be tested on the names of the accessory muscles of deep (forced) ventilation.

·                   Explain the role of surfactant in pulmonary ventilation. Describe infant respiratory distress syndrome. You will not be tested on the treatment.

·                   Describe hiccups.

·                   Describe partial pressure and state how the movement of a gas into a liquid is influenced by its partial pressure.

·                   Explain why the air in the atmosphere is different than the air in your alveoli.

·                   Describe gas exchanges in the body to the level covered in lecture. Do notice the summarizing statement on gas exchanges on page 862.

·                   Name the substance that carries most oxygen in blood.

·                   Define hypoxia and state its symptoms.

·                   State the ways carbon dioxide is transported in blood. Briefly explain how bicarbonate ions form in blood. Briefly explain how the carbonic acid-bicarbonate blood buffer helps regulate blood pH.

·                   State the two regions of the brain involved in respiration control. State the general location of the inspiratory center and the expiratory center how each regulates quiet ventilation. State how the pons respiratory centers influence ventilation. You will not be tested on the names of the specific centers of the medulla or pons.

·                   Explain how the respiratory centers are influenced by pulmonary irritants, pain and emotions, and by voluntary control via the cerebral cortex.

·                   Explain how carbon dioxide levels influence ventilation. State whether carbon dioxide or oxygen is the primary chemical stimulus of increased ventilation.

·                   Describe acidosis and alkalosis. Define hypoventilation and hyperventilation and explain their effect on blood pH.

·                   Describe emphysema. Do read the sections on asthma, tuberculosis, and lung cancer as they are important to your health and career even though they will not be covered on the exam.