In pulmonary ventilation, air flows between the atmosphere and the alveoli of the lungs because of alternating pressure differences created by contraction and relaxation of respiratory muscles.

FUNCTIONS OF RESPIRATORY SYSTEM 1. Gaseous exchange 2. Acid-base balance 3. Phonation 4. Olfaction 5. Effort & evacuation 6. Endocrine functions 7. Venous return 8. Immune functions

Acute Pharyngitis is an inflammation or infection in the throat usually characterized by sore throat

EXPECTED LEARNING OUTCOMES 1. OUTLINE THE PARTS AND FUNCTIONAL SUBDIVISIONS OF THE RESPIRATORY SYSTEM 2. STATE THE TISSUE COMPONENTS OF THE RESPIRATORY SYSTEM AND THE FUNCTIONS OF EACH 3. DESCRIBE THE STRUCTURAL ORGANIZATION OF THE WALL OF THE AIRWAY 4. NAME THE CELL TYPES OF THE RESPIRATORY EPITHELIUM AND STATE THE FUNCTIONS 5. STATE THE PROXIMO-DISTAL STRUCTURAL CHANGES IN THE AIRWAY 6. OUTLINE THE DIVISIONS AND SUBDIVISIONS OF THE LUNG 7. STATE THE FEATURES AND COMPONENTS OF THE FUNCTIONAL UNIT OF THE LUNG 8. NAME THE ALVEOLAR CELL TYPES AND STATE THE FUNCTIONS OF EACH 9. DESCRIBE THE COMPONENTS OF THE THICK AND THIN AIR-BLOOD BARRIER

The respiratory system is a vital biological system responsible for exchanging gases (oxygen and carbon dioxide) between the body and the environment. It includes the lungs and airways (trachea, bronchi, bronchioles), as well as structures like the diaphragm and chest wall. The primary function of the respiratory system is to deliver oxygen to the blood, which then distributes it throughout the body, while also removing carbon dioxide, a waste product of cellular respiration