RESPIRATORY SYSTEM Flashcards
Discuss the primary functions of the respiratory system
- Oxygen & Carbon Dioxide Exchange: Vital for cellular respiration and energy production.
- Acid-Base Balance: Maintains pH through CO₂ regulation.
- Speech Production: Vocal cords in the larynx enable sound.
- Protection & Olfaction: Filters particles and detects odors.
List the major organs of the respiratory system and describe the functions of each.
-Upper Respiratory Tract (URT): Nose, Pharynx (divided into nasopharynx, oropharynx, laryngopharynx), Larynx. Functions to filter, moisten, and warm inhaled air.
-Lower Respiratory Tract (LRT): Trachea, Bronchi, Bronchioles, Alveolar Sacs, Alveoli. Passageway for air and gas exchange.
-Alveoli: Site of gas exchange; lined with surfactant to reduce surface tension.
Describe Key Structures and Functions of the respiratory system
-Nose: Divided by nasal septum into two cavities; warm and moisten inhaled air.
-Pharynx: Passageway for air, food, and liquids; includes pharyngeal tonsils.
- Larynx: Houses vocal cords (two fibrous bands that stretch across the interior of the larynx) for sound production; protected by the epiglottis (partially covers opening into larynx).
oPassageway for air to move to & from the lungs
-Trachea: Air passage held open by C-shaped cartilage rings; blockage can be life-threatening.
- Bronchial Tree: Right and left bronchi divide into bronchioles, ending in alveolar sacs for gas exchange.
-Lungs: Occupy the thoracic cavity; covered by pleura to reduce friction.
What are the Mechanisms of Respiration?
Pulmonary Volumes
-Tidal Volume (TV): Normal amount of air inhaled/exhaled (~500 mL).
-Vital Capacity (VC): Max air that can be inhaled/exhaled fully.
- Expiratory Reserve Volume (ERV): Extra air exhaled after TV.
- Inspiratory Reserve Volume (IRV): Extra air inhaled after TV.
As the tidal volume increases, the ERV and IRV decrease. - Residual Volume (RV): Air remains in the lungs after the most forceful expiration.
Regulation of Respiration
-Brainstem Control: Medulla oblongata regulates involuntary respiration, including respiratory reflexes.
-Chemoreceptors: Respond to changes in CO₂, O₂, and blood pH; located in carotid and aortic bodies.
-Pulmonary Stretch Receptors: Respond to lung expansion
-Voluntary Control: Limited control by the cerebral cortex, mainly during activities like speaking and singing.
Breathing Patterns
o Eupnea: Normal, unlabored breathing.
o Dyspnea: Difficulty in breathing; often a sign of respiratory distress.
o Apnea: Cessation of breathing; may lead to respiratory arrest if prolonged.
o Hyperventilation: Rapid/deep respirations lead to decreased CO₂.
o Hypoventilation: Slow/shallow breathing leads to increased CO₂.
o Respiratory Arrest: Failure to resume breathing after a period of apnea
Compare, contrast, and explain the mechanism responsible for the exchange of gases that occurs during external and internal respiration.
-External Respiration: Occurs in alveoli; O₂ diffuses into the blood, and CO₂ diffuses into the lungs for exhalation.
Gas exchange between air in alveoli and blood in lung capillaries.
-Internal Respiration: Occurs at tissues; O₂ diffuses into cells, CO₂ from cells enters bloodstream.
Gas exchange between blood and tissue cells.
Gas Exchange & Transport
-Oxygen Transport: O₂ binds to hemoglobin in red blood cells (forms oxyhemoglobin).
-Carbon Dioxide Transport: CO₂ travels as carbaminohemoglobin or is dissolved in blood plasma.
-Diffusion: Movement from high to low partial pressure regions, allowing gas exchange.
Protective Features
-Mucosa and Cilia: Mucus, an air purification mechanism, traps irritants such as dust and pollen; cilia beat in only one direction, moving mucus upwards towards the pharynx for removal.
- Pleura: Double-layered membrane around lungs; reduces friction during breathing.
- Goblet Cells: Produce mucus to trap dust and other irritants.
