Medical brain notes 41

  Function of the Respiratory System The primary function of the respiratory system is to  provide  the required  oxygen  and  remove carbon dioxide  from the body. By the removal of carbon dioxide, this system helps  maintain the pH of the blood  at 7.4. An-other important respiratory system function is to help with the  production of sound  (e.g., speaking, singing). The upper part of the respiratory system houses the sensory receptors for  smell,  which are stimulated by chemicals present in the air the body breaths. The respiratory system helps eliminate  some water andheat  as air is breathed in and out. The movement ofthe respiratory muscles and the resultant changes in volume and pressure inside the thoracic cavity  helpincrease venous return and lymphatic drainage.  In ad-dition to these functions, certain cells in the respira-tory system help  activate angiotensin I,  a hormone in-vol...

  The Anatomy of the Respiratory System The respiratory system is made up of passages that conduct air from the environment into the body and respiratory surfaces that are involved in gas ex-change. The respiratory system is classically divided into the  upper  and  lower respiratory tracts.  The upper respiratory tract includes the  nose, nasal cav-ity, paranasal sinus,  and the pharynx  (throat). Thelower respiratory tract (larynx and below) includes all structures below the pharynx and includes the  larynx  (voice box),  trachea  (wind pipe), bronchi, bronchioles,  and the  alveoli  of the lungs (see Figure10.1). Functionally, the respiratory system can be classified as the conducting part and the respiratory part. The conducting part includes those structures that are only involved in conducting the air from the atmosphere to the lungs. All structures from the nose to the last part of the bronchioles belong t...

  LOWER RESPIRATORY TRACT The Larynx The larynx, or voice box (see Figure 10.6), is the re-gion that connects the pharynx to the trachea (wind-pipe). It can be felt just below the jaw in the upper, anterior part of the neck. The larynx is largely carti- lage, with ligaments and muscles attached. The  epiglottis, thyroid cartilage,  and  cricoid cartilage  are the larger cartilages. The epiglottis, located inter-nally close to the base of the tongue, is shaped like a shoehorn. With each swallow, it moves posteriorly to close the narrow opening of the larynx (the  glottis ) to prevent entry of food into the larynx. The thyroid cartilage is shaped like a shield and is commonly known as the Adam’s apple. It forms the anterior and lateral wall of the larynx. Superiorly, lig-aments attach the thyroid cartilage to the hyoid bone. Inferiorly, ligaments attach it to the cricoid cartilage. The cricoid cartilage is ring-shaped and is, in turn, inferiorly attached to t...

  The Anatomy of the Respiratory  System The respiratory system is made up of passages that conduct air from the environment into the body and respiratory surfaces that are involved in gas ex-change. The respiratory system is classically divided into the  upper  and  lower respiratory tracts.  The upper respiratory tract includes the  nose, nasal cav-ity, paranasal sinus,  and the pharynx  (throat). Thelower respiratory tract (larynx and below) includes all structures below the pharynx and includes the  larynx  (voice box),  trachea  (wind pipe), bronchi, bronchioles,  and the  alveoli  of the lungs (see Figure10.1). Functionally, the respiratory system can be classified as the conducting part and the respiratory part. The conducting part includes those structures that are only involved in conducting the air from the atmosphere to the lungs. All structures from the nose to the last part of the bronchioles be...