Resp Sys Lab
Organs of the respiratory system include the nose and nasal passages, the paranasal sinuses, the pharynx (all included in the upper respiratory system), and the glottis, larynx, trachea, bronchi, and lungs (of the lower respiratory system). The diaphragm, intercostal muscles, pectoralis minor, and serratus anterior muscles also play an important role in ventilation (inspiration and expiration).
What tissue (illustrated below) lines most of the upper and lower respiratory tract?
Be able to name the cavities and membranes associated with the lungs.
The larynx includes nine cartilages (3 single cartilages [epiglottic, thyroid, & cricoid], and 3 paired ones [arytenoid, corniculate, a& cuneiform]), as well as the true and false vocal folds.
What trends occur in respect to cartilage within the trachea and bronchial tubes? Distinguish between primary, secondary, and tertiary (segmental) bronchi. Describe the differences between the epithelial lining of the bronchioles, terminal bronchioles, respiratory bronchioles, and alveoli.
The top of this cross section of the trachea is the anterior portion, while the bottom includes the trachealis muscle, which holds the posterior ends of the C-shaped cartilages in place. The esophagus would be below this section, if it were shown.
Occasionally, the cartilage rings overlap, as shown below. Numerous mucous glands are often seen between the cartilage rings and the epithelium.
None of these bronchioles contain cartilage, as is found in the primary, secondary, and tertiary bronchioles.
Be able to compare the differences in gas volumes, percentages, and pressures that result in gas exchange in ventilation, external respiration, and internal respiration. What are the functions of alveolar macrophages and type II alveolar cells? What is the relationship between gas exchange and cellular respiration? What factors cause blood to release oxygen from hemoglobin in the body tissues, and release carbon dioxide in the lung tissues? In what ways are these gases transported in the blood, and what percentages are transported by each mechanism (compare the following seven illustrations)?
Type I alveolar cells allow respiratory gases to diffuse in and out of the capillaries. Type II alveolar cells produce surfactant, a material that coats the inside of the alveoli and lowers surface tension. This prevents the alveoli from collapsing upon exhaling. Macrophages phagocytize microbes and dust particles inhaled into the lungs.
Atmospheric pressure at sea level is normally considered to be 760 mm of mercury (Hg). Each gas exerts a pressure equal to its percentage within the air (Dalton's Law). Oxygen comprises 20.84% of the atmosphere, Nitrogen comprises 78.62%, and water vapor (0.50%), carbon dioxide (0,04%), pollutants, etc., comprise the remaining 1%. The pCO2 = 0.3 mm Hg. Exchange of gases depends upon the partial pressure of each component. The partial pressure of Oxygen (pO2) is approximately 159 mm Hg at sea level, and decreases with altitude. Hemoglobin has a high affinity for oxygen, and 98.5% of O2 is carried in the bloodstream as oxyhemoglobin (HbO2). The remaining 1.5% is dissolved in the plasma.
Be able to explain the significance of saturation levels of oxygen in the blood. What are the Bohr effect and reverse Bohr effect, and how do changes in CO2 levels, pH and temperature influence oxygen saturation?
Approximately 70% of CO2 is transported as HCO3- (bicarbonate ions), 23% as carbaminohemoglobin (attached to the globin of Hb). The remaining 7% is dissolved in plasma.
RBCs contain an enzyme (carbonic anhydrase), that combines CO2 and H2O to form carbonic acid H2CO3. This acid dissociates into H+ and HCO3-. Hb attracts the H+ to form acid Hb (a weak acid), and the HCO3 diffuses out of the RBCs to combine with Na+ as sodium bicarbonate (baking soda). Cl- diffuses into the RBCs in the capillaries through chloride channels in the RBC membranes.
In the lungs, these processes are reversed, and the CO2 is released into the atmosphere, while Oxygen diffuses into the blood.
Be able to explain the volumes shown below, and give the significance of each.
What changes in the lungs and respiratory volumes occur with emphysema?
