Anatomy and Physiology Respiratory System Questions and Answers with complete solutions

Anatomy and Physiology Respiratory System Questions and Answers with complete solutions ___% of tidal volume remains in _____ - ANS- 30, conducting zone ___% oxygen bound to hemoglobin (Hb) - ANS- 98.5 ___% oxygen dissolved in plasma - ANS- 1.5 2 types of alveolar epithelial cells - ANS- type I - main site of gas exchange, type II - secrete alveolar fluid (surfactant - reduces tendency of sacs to collapse) 3 basic steps of respiration - ANS- ventilation (breathing), external (pulmonary) respiration, internal (tissue) respiration 3 groups of respiratory center - ANS- 1. medullary rythmicity area (medulla) 2. pneumotaxic area (pons) 3. apneustic area (pons) 4 effects on rate of pulmonary and systemic gas exchange - ANS- 1) partial pressures of gases, 2) surface area available for gas exchange (alveoli, RBC), 3) diffusion distance (respiratory membrane very thin, capillaries), 4) molecular weight MW and solubility of gases (lower MW diffuses faster, solubility varies) accessory muscles aiding inhalation during exercise or forced ventilation - ANS- sternocleidomastoids, scalene muscles, pectoralis minor actual site of gas exchange in lungs - ANS- across alveoli walls after inhalation, pressure is ____ in the lungs than in atmospheric pressure - ANS- greater air moves down in ____ - ANS- pressure gradient alveolar sac - ANS- 2 or more alveoli sharing a common opening apneustic area of respiratory center - ANS- also coordinates between inhalation and exhalation. stimulates inspiratory area, causes long deep inspiration, signals from pneumotaxic area overrides apneustic area stimulation as lung volume increases, _____ pressure drops - ANS- alveolar/intrapulmonic bicarbonate ions - ANS- 70% of CO2 transported in plasma as HCO3 (bicarbonate) binding of one ___ to a heme group causes a ___ change that makes binding of other ___ molecules easier - ANS- O2, shape, O2 Bohr effect - ANS- factors that effect PO2 saturation - pH, PCO2, temperature Boyle's Law - ANS- movement of air into and out of lungs, pressure of a gas in a closed container is inversely proportional to the volume of the container carbamino compounds - ANS- about 23% of CO2 combines with amino acids of plasma proteins including Hb carbonic anhydrase - ANS- enzyme that forms carbonic acit from water and CO2 cardio system and resp system cooperate to supply body cells with ____ and to eliminate ___ - ANS- O2, CO2 cardio system transports ____ - ANS- respiratory gases chemoreceptor regulation - ANS- central chemoreceptors are CNS receptors in medulla, (monitor levels of CO2 and H+), peripheral chemoreceptors in walls of aorta arch and carotid arteries (monitor levels of O2, CO2, H+), hypercapnia or hypoxia stimulate inspiration area conducting zone - ANS- moves air to lungs conducting zone is considered ___ - ANS- anatomic (respiratory) dead space because air in these regions does not undergo respiratory gas exchange contraction of diaphragm and intercostals causes ____ - ANS- thoracic cavity to expand. parietal pleura lining expands, visceral pleura tightly adhered to parietal pleura is pulled along which pulls lungs open. cortical influences - ANS- cerebral cortex allows some conscious control of respiration, breath holding limited by overriding stimuli of increased H+ and CO2, if fainting occurs from breath holding regular breathing occurs when consciousness is lost Dalton's law - ANS- governs movement of gas down pressure gradients deoxyhemoglobin - ANS- without oxygen bound hemoglobin dissolved CO2 accounts for ___% of CO2 in blood - ANS- 7 each iron atom can bind one ___ molecule - ANS- O2 equal air pressure before inhalation - ANS- ~760 mm Hg exhalation is normally ____ - ANS- passive exhalation process - ANS- elastic recoil of chest wall and lungs bring back to original shape, diaphragm relaxes and returns to dome shape, external intercostals relax and ribs drop down, only active during forceful breathing expiratory reserve volume (ERV) - ANS- inhale normally and exhale forcefully, additional 700 ml female, 1200 ml male external (pulmonary) respiration - ANS- exchange of gases between aveoli and blood external respiration - ANS- step 2 of respiration - Dalton's Law, Henry's Law. exchange of gases between alveoli and blood external respiration in lungs - carbon dioxide - ANS- CO2 diffuses from deoxygenated blood in pulmonary capillaries (PCO2 45mmHg) into alveolar air (PO2 40mmHg), continues until PCO2 blood reaches 40 mmHg external respiration in lungs - oxygen - ANS- O2 diffuses from alveolar air (PO2 105 mmHg) into blood of pulmonary capillaires (PO2 40 mmHg), diffusion continues until PO2 of pulmonary capillary blood matches PO2 of alveolar air external respiration occurs ___ - ANS- by passive diffusion following rules of Dalton's and Henry's laws