We noted in Chapter 10 that dogs are believed to benefit when they pant by breathing at a fixed resonant frequency. Although dogs inhale and exhale exclusively through the nose when not under heat stress, they exhale orally to some (variable) extent when panting. Air exhaled by way of the mouth remains nearly at deep-body temperature. Explain how a panting dog could vary its rate of evaporative cooling—even while breathing at a fixed frequency—by modulating how much it exhales by way of its nose or mouth.

What is the RER of an individual with an oxygen consumption of 220 ml/min and a carbon dioxide production of 182.6 ml/min? Report your answer to 2 decimal points. QUESTION 29 What percent of the individual's oxygen consumption in the previous question is being used to combust carbohydrate for energy? Round your answer to the nearest whole number and answer with a number only as units are given in the question.

Which of the following combinations would all result in an increase in stimulation to breathe? Group of answer choices decrease in PCO2 : increase in H+ : decrease in PO2 increase in PCO2 : increase in H+ : decrease in PO2 decrease in PCO2 : decrease in H+ : decrease in PO2 increase in PCO2 : decrease in H+ : increase in PO2 decrease in PCO2 : decrease in H+ : increase in PO2

Describe what happens in the respiratory system when you run to catch a bus by placing the following in order (#1-7). Consider that the running will have caused an increase in cellular respiration, which results in an increase in CO2 (this is the change in the variable). The increase in CO2 will be detected by the brain, which will ultimately cause an increase in ventilation. Blood CO2 levels increased and O2 levels decreased.   Increased ventilation results.   Chemoreceptors detect decreased O2 and increased concentration of CO2/decreased pH.   Return to normal CO2 and O2 levels.   Respiratory centers increases its stimulation of spinal nerves (phrenic and intercostal).   Increased frequency and degree of contraction of respiratory muscles.   Central and peripheral chemoreceptors stimulate the respiratory centers in the brainstem.   Increased cellular respiration in response to the running.

Why does respiration become more challenging for organisms as they become larger (in other words which of the following is/are true about respiratory demand)? I. total metabolic demand increases in proportion to body mass (volume) II. a higher surface area to volume ratio decreases the effectiveness of using diffusion alone III. a lower surface area to volume ratio decreases the effectiveness of using diffusion alone

Ventilators are often used for individuals with COVID-19 to increase the rate of diffusion of gases across the alveoli. Ventilators could increase the rate of diffusion by impacting which factor of Fick’s law of membrane diffusion: a   decreasing the diffusion coefficient (D) b   decreasing surface area (A) c   increasing the partial pressure difference (P1-P2) d   increasing the diffusion distance  e   all of the above

Respiratory epithelial cells are involved in mucus maintenance within the airway. Explain theroles of pumps, channels, and carriers in this process – emphasize CFTR’s role in chloridepassage, and how chloride triggers water movement which maintains the mucus fluidity in theairway.

Because CO2 and H+ are linked in a dynamic equilibrium, PCO2 changes will affect both H+ and HCO3- levels.  In the scenarios below, use "up" arrow or "down" arrow to indicate changes to PCO2, H+, and HCO3-.                                                       If ventilation increases, plasma PCO2 ______________, H+ ______________, and HCO3- ___________________                                   If ventilation decreased, plasma PCO2 _____________, H+ ______________, and HCO3- __________________