Respiratory System – ch. 23 – Flashcards

Which is the correct sequence of events for inhalation? 1. pressure of the atmosphere is greater than the pressure within the thorax 2. volume of the thorax increases and the pressure within the thorax decreases 3. the diaphragm contracts 4. the phrenic nerve fires 4, 3, 2, 1 1, 2, 3, 4 4, 3, 1, 2 1, 4, 3, 2 2, 1, 3, 4

A bronchopulmonary segment is directly supplied by a ______________________. primary bronchus. secondary (lobar) bronchus. tertiary (segmental) bronchus. respiratory bronchiole. alveolar duct.

Surfactant lowers the surface tension of alveolar fluid; it is produced by alveolar macrophages. fibroblasts. type I alveolar cells. type II alveolar cells. goblet cells.

After holding our breath briefly, what eventually forces us to take a breath? decreasing oxygen levels. increasing oxygen levels. decreasing carbon dioxide levels. increasing carbon dioxide levels. increasing blood pH.

Which of the following is a passageway for air, food and water? Trachea Esophagus Pharynx Larynx Paranasal sinuses

Which of the following statements is NOT correct? The lungs surround the mediastinum. Air normally fills the pleural cavity. The visceral pleura covers the lungs. The parietal pleura lines the thoracic cavity. The parietal and visceral pleura are separated by the pleural cavity.

True or false. As the bronchial tree branches from bronchi to bronchioles, cartilage decreases while smooth muscle increases.

Which of the following is the dominant method of carbon dioxide transport? Dissolved in plasma as a gas Dissolved in plasma as bicarbonate ions Diffusion Bound to hemoglobin Bound to oxygen

True or false. In a resting person, more oxygen molecules are attached to each hemoglobin molecule in blood in the pulmonary arteries than in the pulmonary veins.

Which structure prevents food or water from entering the trachea? Arytenoid cartilage Epiglottis Paranasal sinus Nasopharynx Thyroid cartilage

True or false. As you sit quietly reading these questions, you use the diaphragm, external intercostal, and scalene muscles.

All of the following affect the rate of pulmonary and systemic gas exchange EXCEPT external air temperature. partial pressure difference of the gases. surface area available for gas exchange. diffusion distance. molecular weight and solubility of the gases.

In external respiration __________, while __________ occurs in internal respiration. oxygen moves from the alveoli to the pulmonary capillaries; carbon dioxide moves from the pulmonary capillaries to the alveoli. oxygen moves from the alveoli to the pulmonary capillaries; oxygen moves from the pulmonary capillaries to the alveoli. carbon dioxide moves from the alveoli to the pulmonary capillaries; carbon dioxide moves from the pulmonary capillaries to the alveoli. oxygen moves from the alveoli to the pulmonary capillaries; oxygen moves from the tissues to the systemic capillaries. oxygen moves from the alveoli to the pulmonary capillaries; carbon dioxide moves from the tissues to the systemic capillaries.

Hemoglobin can unload more oxygen in metabolically active tissues than in tissues at rest because

Exhalation begins when Inspiratory muscles relax Diaphragm contracts Blood circulation is the lowest Both Inspiratory muscles relax and Diaphragm contracts All of these choices

True or false. Some structures in both the upper and lower respiratory tracts serve as sites for gas diffusion.

Which of the following is the primary gas exchange site? Trachea Alveolus Bronchiole Bronchus Nasal sinuses

Which of the below tissues maintains open airways in the lower respiratory system? ciliated pseudostratified columnar epithelium with goblet cells mucus membrane bone stratified squamous epithelium with keratin hyaline cartilage

Which of the following indicates the direction of diffusion of gases at the alveoli of the lungs? Oxygen out of blood, Carbon dioxide out of blood Oxygen into blood, Carbon dioxide into blood Oxygen out of blood, Carbon dioxide into blood Oxygen into blood, Carbon dioxide out of blood

True or False. Unlike capillaries in the rest of the body, pulmonary capillaries vasoconstrict when localized hypoxia occurs.