Question | Answer |
What structures do the URT contain? | Everything located outside of the thoracic cavity; from the larynx up |
What structures do the LRT contain? | Everything located inside the thoracic cavity; from the trachea down |
What is the purpose of the nasal cavity? | Moisten and warm inhaled air, mucus in the nasal cavity collects inhaled dust, preventing it from entering the lungs |
What Is the pharynx? | Muscular tube, commonly called the "throat" |
What structures are in the pharynx? | Nasopharynx, Oropharynx, & Laryngopharynx |
What is the nasopharynx? | Lies just behind the soft palate, contains openings for the Eustachian tubes |
What is the Oropharynx? | Space between the soft palate and base of the tongue; contains tonsils |
What is the Laryngopharynx? | Passes dorsal to the larynx & connects to the esophagus |
What does the larynx do? | Prevent food & liquids from entering the trachea; acts a passageway between the pharynx and trachea; also produces sound |
What is the trachea? | Large tube supported by C-shaped rings of cartilage; often called the windpipe |
What is the epiglottis responsible for? | Directing food and liquids into the esophagus during swallowing. |
What do the vestibular folds do? | Prevent food from entering the airway |
What are the Bronchi? | Large tubes (one for each lung) that serve as a passageway for air |
How many lobes does the right lung have? | Three |
How many lobes does the left lung have? | Two - to allow room for the heart |
What is the result of the right bronchus being wider & more vertical than the left? | It is the most likely location for aspirated (inhaled) food particles and small objects to lodge |
What is the Carina? | Cartilaginous ridge at the end of the trachea |
What are the bronchioles? | Small airways that lack supportive cartilage |
Why do the lung passages exist? | To serve the alveoli |
What occurs within the alveoli? | Gas exchange |
What are the alveoli wrapped in? | Fine mesh of capillaries that allow for efficient gas exchange |
What must happen before a gas enters or leaves a cell? | Must be dissolved in a liquid |
What is the alveolus coated in? | Thin layer of fluid |
What does the thin layer of fluid that coats the alveolus contain? | Surfactant |
What is the purpose of surfactant? | Helps reduce the surface tension (for of attraction between water molecules) to keep the alveolus form collapsing as air moves in & our during respiration |
What is the pleura? | Space between the visceral & parietal pleurae; the two membranes are normally separated only by a film of slippery pleural fluid |
What are the two parts of pulmonary ventilation? | Inspiration & expiration |
What do both inspiration & expiration depend on? | Respiratory muscles; mainly the diaphragm
Difference between air pressure within the lungs and outside the body |
What respiratory muscles are used during inspiration? | External intercostal pull the ribs upward & outward; internal intercostals help elevate the ribs; the diaphragm contracts, flattens & drops, pressing the abdominal organs downward and enlarging the thoracic cavity. Air rushes in |
During times of forced/labored breathing, what accessory muscles of respiration assist with breathing? | Sternocleidomastoids & scalenes (muscles of neck), pectoralis minor (chest muscle) contact to help elevate the chest |
What is the inspiration center & where is it located? | Primary respiratory center located in the medulla |
What is the pneumatacic center? | Prevents lung overinflation |
What is the expiratory center and where is it located? | Used for forceful exhalations located in the medulla |
What are the factors that influence breathing? | Oxygen levels, hydrogen ions (pH), stretch, pain & emotion, irritants |
What happens when a persons O2 levels get low? | Peripheral chemoreceptors (in corotid & aortic bodies) detect low blood levels of oxygen & signal the medulla to increase rate & depth of respirations to bring in more oxygen |
What drives pressure & airflow? | Atmospheric pressure |
What are the factors that affect airflow? | Pulmonary compliance (elasticity), alveolar surface tension (the inner surface of each alveoli) is covered with a thin film of water, which is necessary for gas exchange |
What is a pneumothorax? | When thoracic wall is punctured, causing negative pressure which causes thelung recoil & collapse |
What is tidal volume? | Amount of air inhaled and exhaled during quiet breathing |
What is inspiratory reserve volume? | Amount of air inhaled using maximum effort after normal inspiration |
What is apnea? | Temporary cessation of breathing |
What is dyspnea? | Labored or difficulty breathing |
What is hyperventilation? | Increased rate & depth of respirations, resulting in lowered blood levels of CO2; often results from anxiety |
What is orthopnea? | Labored breathing that occurs when the a person is lying down flat but improves when standing or sitting up; classic symptom of left ventricular failure |
What does gas exchange depend on? | Differences in pressure |
Explain gas exchange | The partial pressures of O2 & CO2 vary between the air we breathe, the alveoli, arterial blood, and venous blood. These variations in pressure allow the body to absorb oxygen and expel CO2 |
What is the primary regulator of respiration? | Carbon dioxide |
What is the primary way that O2 is transported in the blood? | In the form of oxyhemoglobin |
How is most of the CO2 in the body transported? | In the form of bicarbonate ions |