BSC 2086 1st EditionExam 4 Study Guide1. What are the five functions of the respiratory system?a. Makes available extensive gas exchange surface area between the circulating blood and airb. Moves air to and from the exchange surfaces of the lungsc. Provides protection of the respiratory surfaces from the outside environmentd. Makes soundse. Plays a role in olfactory sense2. What are the components of the respiratory system? Which parts are shared with the digestive system? Which parts are in the upper respiratory system? Which parts are in the lower respiratory system?a. Upper respiratory system: above the larynx i. Frontal sinusii. Nasal cavityiii. Sphenoidal sinusiv. Internal naresv. Tonguevi. Nasal conchae vii. Nose b. Lower respiratory system: below the larynx i. Tracheaii. Esophagusiii. Bronchusiv. Bronchiolesv. Lungs c. The digestive system shares the oral cavity and the pharynx. 3. What is the difference between the conducting portion and respiratory portion of the respiratory tract?a. Conducting portion: from nasal cavity to terminal bronchiolesi. Involved in ONLY moving air into and out of the lungsii. No gas exchange occurs in this portion iii. Lined by the respiratory mucosa 1. Consists of an epithelial layer and an areolar layer known as the lamina propria b. Respiratory portion: respiratory bronchioles and alveoli i. Alveoli are air filled pockets found within the lungs1. Gas exchange takes place here4. What is the difference between the respiratory epithelium, respiratory mucosa, and the alveolar epithelium? What cell types are found in each of these structures?a. Respiratory epitheliumi. In order for gases to exchange efficiently:1. Alveoli walls must be < 1 µm (very thin)a. Allows for movement of gases through the walls 2. Surface are must be very big, about 35 times the surface area of the body b. Respiratory mucosai. Lines conducting part of the respiratory systemii. Consists of an epithelial layer and an areolar layer (lamina propria)iii. Lamina propria 1. Underlying layer of areolar tissue which supports the respiratory epithelium2. Part of respiratory mucosa in the conducting portion of respiratorytract3. Contains mucous glands that secrete onto the epithelial surface in the upper respiratory tract, trachea and bronchi4. Contains smooth muscle cells that encircle lumen of bronchioles in the conducting portion of the lower respiratory systemc. Alveolar epithelium i. Delicate simple squamous epithelium because it is a single later of flat epithelial cellsii. Mixture of scattered and specialized cells that line exchange surfaces of alveoli5. What filtration mechanisms exist in the respiratory system?a. Mucous cells and mucous lands make the mucus that bathes exposed surfacesb. Cilia can be described as a mucus escalator, which sweeps debris trapped in the mucus towards the pharynx c. Large particles removed through filtration in nasal cavityd. Small particles that arrive to the lungs are engulfed by alveolar macrophages 6. What is the function of the epiglottis? Where is it located and why is it important?a. The epiglottis prevents entry of food and liquids into the trachea by folding over the glottis during swallowing. b. It is one of the cartilages of the larynx 7. Where are the vocal folds located? How is sound produced by the vocal cord?a. Vocal folds located on the larynx b. Sound is produced by air passing through the glottis, which vibrates the vocal folds c. Slender, short folds produce a higher pitchd. Thicker, longer folds produce a lower pitche. Vocal folds involved with sound are known as vocal cords8. What is the trachealis muscle? Where is it located and how is it regulated?a. The trachealis muscle connects the ends of each tracheal cartilage.b. Contraction of this muscle reduces the diameter of the tracheac. Regulated by sympathetic divisioni. Relaxation of trachealis muscle seen with sympathetic stimulation9. Why do objects that enter the trachea most often enter the right primary bronchus as oppose to the left primary bronchus? What are the differences between the right and left lung?a. Right and left primary bronchi are separated by an internal ridge known as the carina b. Differences:i. Right primary bronchus is larger in diameterii. Right primary bronchus descends at a steeper angle which is the reason for which most foreign objects entering the trachea enter the right primary bronchus10. What is the difference between bronchitis, asthma, respiratory distress syndrome, and pneumonia? What are the causes of each of these conditions?a. Bronchitisi. Inflammation of the bronchial walls which results in constriction and difficulty breathingb. Asthmai. Excessive stimulation of smooth muscle and vasoconstriction causes folds to form in bronchiole mucosa1. This causes further restriction of airflow 2. Decreased oxygen levels reaching alveolic. Respiratory distress syndromei. Difficulty breathing due to alveolar collapseii. Caused by failure of pneumocytes type II to make enough surfactant iii. Must take deeper breathes in order for alveoli to openiv. Seen in premature infants whose lungs have yet to develop1. Produce too little or not any surfactant d. Pneumonia i. Inflammation of lobulesii. Causes fluid to leak into alveoli and constrict respiratory bronchiolesiii. Affects the functioning of the respiratory membrane11. How are the bronchioles structurally different than the bronchi? What is the significance of this difference?a. Structure of Bronchii. Walls of primary, secondary and tertiary bronchi contain progressively more smooth muscle but less cartilageii. An increase in smooth muscle tension will affect constriction and resistance of airways b. Structure of Bronchiolesi. No cartilageii. Filled with smooth muscle c. More smooth muscle means the ability to regulate the airflow and resistance in the lungs i. Bronchodilation: dilation of the bronchial airways which are caused by activation of the sympathetic ANS1. Reduces resistanceii. Bronchoconstriction: constriction of bronchi caused by activation of parasympathetic ANS1. Causes histamine release (allergic reactions)12. What are the components of the respiratory membrane? Why does diffusion of gases occur at the respiratory membrane?a. Thin membrane of alveoli where gas exchange occursi. Three layers:1. Squamous epithelial cells lining alveolus2. Endothelial cells lining adjacent capillary3. Fused basement membranes between alveolar and endothelial cells b. Diffusioni. Very fast across
View Full Document
Unlocking...