Answer Happy

Effects of Hyperventilation and Diving Jinn Li is an Ama ("sea woman") sitting on the edge of her boat preparing to dive into the frigid water off the coast of a remote Japanese island. To prepare for her shellfish collecting dive Jinn Li hyperventilates by taking shallow inhalations for several minutes (30 breaths/min), then she jumps into the water with only a knife and bag. Neither she nor her coworkers use SCUBA or any other technology to help them stay submerged for long periods of time; however, they are able to work underwater for a longer period of time than if they simply breathed deeply before diving. As Jinn Li is about to surface, she sees a valuable specimen waiting to be collected. Without regard to her internal timing device (i.e., the voice of experience). Jinn Li swims down to collect the specimen, and upon her ascent she unexpectedly faints. Fortunately, she is near the surface and is rescued before drowning. Use the class notes and the graph below to help answer the questions posed.
100 P 02 (mm Hg) 80 60 40 20 0 P CO2 w/o hyper- ventilation QUESTIONS P02 1 Involuntary respiratory command issued Dizziness Disorientation Fainting Death: PC02 W/ hyperventilation Tissue Hypoxia Time (minutes) 1. What effect does hyperventilation have on the concentration of carbon dioxide in the blood just prior to diving? On the pH of blood (hint: review the reactions between CO₂ and H₂O)? 80 P C02 (mm Hg) 60 55 40 20
2. What molecule in the blood must build to a critical level to cause inhalation? Give the specific region of the brain that monitors the concentration of this molecule in the blood. 3. Cellular (oxidative) respiration produces the molecule identified in question two. What type of tissue would be giving off much of this molecule during a strenuous dive? 4. Explain why the involuntary respiratory command was postponed by hyperventilation.
5. What caused Jinn Li's dizziness, disorientation and loss of consciousness?