BIPN 106, Comparative Physiology, Winter 2014 Question 1 a. (2) What is the common name for animals in each of these two genera? Mirounga is an elephant seal, and Onchorhynchus is a king salmon. FOR THE REST OF THIS PAGE, BRIEFLY, but thoroughly, support each of your predictions. (If you can't make the prediction, state what additional information you would need.) b. For each of the following physiological features, predict what you would find in Mirounga and compare it with what you would expect to find in Onchorhynchus when both animals were swimming at a depth of 150 meters off the coast of southern Alaska. i. (4) pH of arterial blood Mirounga can't breathe when it's submerged, so it can't acquire more O2 or release CO2. In contrast, Onchorhynchus is breathing normally. As a result, the pH of Mirounga's blood would be lower than the pH in Onchorhynchus caused by accumulation of CO2 and an increase in blood lactate. ii. (4) PCO2 of arterial blood The PCO2 of arterial blood in Onchorhynchus will have its normal, low value because Onchorhynchus is breathing normally. The PCO2 of arterial blood in Mirounga will be high because it has no way to release CO2 into the environment, so as time goes on the arterial PCO2will increase more and more as blood recirculates through the tissues and CO2 is added. iii. (4) Osmolarity of interstitial fluid (lymph) The osmolarity of interstitial fluid will be very similar in the two species--approximately 300 mOsmolar. iv. (4) Lactate concentration in skeletal muscles of the body wall As part of Mirounga's diving reflex, arteries carrying blood into its skeletal muscles will be strongly vasoconstricted, so blood flow through the skeletal muscles will be greatly reduced. Lack of O2 will shift muscle fibers to producing ATP via glycolysis, which also produces lactic acid (lactate is the deprotonated form of this acid). The combination of glycolytic production of ATP and reduced blood-flow through the muscles will greatly increase their lactic acid concentration. Onchorhynchus has no such problems; it is breathing normally. c. (6) Predict, if you can, the pH of arterial blood in Mirounga that has been at the surface of the ocean for 15 minutes with the pH of arterial blood in Onchorhynchus that is swimming 5 feet below the surface As a water-breather, Onchorhynchus has no problem releasing CO2 into its environment (typically across the surface of its gills. before the blood travels to the tissues), so PCO2 is normally low in its arterial blood, and the pH is relatively high. Mirounga is an air-breather and has a higher PCO2 because it has a greater difficulty in releasing CO2 into its environnment. As a result, the pH of Mirounga's arterial blood is lower than in the salmon's blood. https://www.coursehero.com/file/8920843/Midterm-2-Solutions-2014/This study resource wasshared via CourseHero.comCopyright 2014, Kathleen French and UCSD. For the private use of students in BIPN 106, Winter Quarter 2014. Any other use is prohibited. Question 2 a. (1) What is the common name of Rhinodon? The whale shark. b. (4) To which phylum and class do each of these two animals belong? Rhinodon: Phylum = Chordata, class = Chondrichthyes Hypsipops: Phylum = Chordata, class = Osteichthyes c. Rhinodon and Hypsipops have both just eaten a lot of their favorite foods (see description above). i. (5) Consider the osmolarity of the body fluids in each of these two animals, and predict whether this large meal is likely to disturb the osmolarity of the body fluids in either of them. BRIEFLY support your answer, and if you can't make this comparison, state what additional information you would need. The osmolarity of the shark's body fluids is likely to be 900 mOsm or higher. Eating the marine invertebrates, which are iso-osmotic with sea water (1000 mOsm), will cause little change. In contrast, the osmolarity of the garibaldi's body fluids will be close to 300 mOsm, so eating the marine invertebrates causes a big salt load for e garibaldi. ii. (5) Consider the [Na+]plasma of each of these two animals, and predict whether this large meal is likely to disturb the [Na+]plasma in either of them. BRIEFLY support your answer, and if you can't make this comparison, state what additional information you would need. The [Na+] of extracellular fluids in both fishes is approximately 150 mM, whereas the [Na+] of extracellular fluid in the invertebrates is closer to 450 mM. As a result, both the shark and the garibaldi will be consuming excess Na+, which they will need to excrete. iii. (5) A Panulirus interruptus (Mexican spiny lobster) that is living at the bottom of the ocean off the coast of La Jolla eats a meal made up of the same kinds of molluscs and annelids that the garibaldi does. Would this meal be likely to disturb the osmolarity or the [Na+] of its extracellular fluid? BRIEFLY support your answer, and if you can't make this comparison, state what additional information you would need. Like its prey, Panulirus (an arthropod) is iso-osmotic with sea water, and the [Na+] in its extracellular fluids is about the same, so eating marine invertebrates won't disturb either the lobster's osmolarity or its [Na+]. d. (6) Compare the major organ(s)--if any--that are responsible for regulating osmotic and ionic concentrations of extracellular fluids in these three species. Regulatory organ(s) if any (Write "none" if there aren't any) Rhinodon gills, rectal salt gland, kidneys Hypsipops gills, kidneys Panulirus none , it's an osmoconformer and an ionoconformer https://www.coursehero.com/file/8920843/Midterm-2-Solutions-2014/This study resource wasshared via CourseHero.comCopyright 2014, Kathleen French and UCSD. For the private use of students in BIPN 106, Winter Quarter 2014. Any other use is prohibited. Question 3 Water gain Water loss drinking respiration eating food excretion (urine & feces) metabolic water from oxidative metabolism evaporation from body surface b. (6) What is/are the principal organs that each of these animals is likely to use in regulating the osmolarity and solute concentrations in their extracellular fluids? Regulatory organ(s) if any (Write "none" if there aren't any) lizard kidneys, nasal salt gland insect-eating bat kidneys turkey vulture kidneys, nasal salt gland c. (6)What is the likely osmolarity of the following two body-fluid compartments in these three animals? Extracellular fluids