BIOL 3030 QUIZ QUESTIONS 2| 33 QUESTIONS AND ANSWERS

What is the correct order of processes involving the movement of oxygen from the environment to mitochondria in vertebrates? diffusion in tissues, cellular respiration, diffusion at respiratory surface circulation, cellular respiration, diffusion in tissues circulation, ventilation, cellular respiration ventilation, circulation, cellular respiration ventilation, diffusion in tissue, circulation ventilation, circulation, cellular respiration In which location would you expect the oxygen concentration to be the lowest? within tissues the blood the heart the lungs the environment within tissues Gas exchange is more difficult for aquatic animals with gills than for terrestrial animals with lungs because gills collapse in air gills allow only unidirectional transport water contains much less oxygen per unit volume than air gills have less surface area than lungs water is less dense than air water contains much less oxygen per unit volume than air At an atmospheric pressure of 870 mm Hg with 21 percent oxygen, the partial pressure of oxygen is _____. 182 mm Hg 219 mm Hg 127 mm Hg 100 mm Hg 182 mm Hg When that air in a testing chamber is specially mixed so that its oxygen content is 10 percent and its overall air pressure is 400 mm Hg, then PO2 is _____. 21 mm Hg 4 mm Hg 400 mm Hg 82 mm Hg 40 mm Hg 40 mm Hg Carbon dioxide levels in the blood and in cerebrospinal fluid affect pH of these fluids. This enables the organism to sense a disturbance in gas levels as _____. the brain alters the pH of the cerebrospinal fluid to force the animal to retain more or less carbon dioxide the medulla oblongata is able to control the concentrations of bicarbonate ions in the blood stretch receptors in the lungs cause the medulla oblongata to speed up or slow breathing the brain directly measures and monitors oxygen levels and causes breathing changes accordingly neurons in contact with cerebrospinal fluid monitor pH and use this measure to control breathing neurons in contact with cerebrospinal fluid monitor pH and use this measure to control breathing Under identical atmospheric conditions, freshwater ____. can hold 10-40 times more oxygen than air can hold 10 - 40 times more carbon dioxide than air has more oxygen than seawater has less oxygen than seawater has more oxygen than seawater Determine the rate of diffusion (cm3/min or mL/min) in the gas-exchange organ of an air-breathing animal where the area for gas exchange in the lung is 2 cm2, the diffusion constant is 0.08 cm2/min, the PO2 (partial pressure of oxygen) of the air in the lung is 140 mm Hg, the PO2 in blood flowing into the lung is 90 mm Hg, and the thickness of the gas exchange membrane is 0.0001 cm. 125 80,000 10,000,000 32,000 80,000 Countercurrent exchange is evident in the flow of _____. air within the primary bronchi of a human and the blood within the pulmonary veins blood in the dorsal vessel of an insect and that of air within its tracheae water across the gills of a fish and the blood within those gills water across the skin of a frog and the blood flow within the ventricle of its heart water across the gills of a fish and the blood within those gills Air rushes into the lungs of humans during inhalation because ____. pulmonary muscles contract and pull on the outer surface of the lungs the volume of the alveaoli increases as smooth muscles contract a positive respiratory pressure is created when the diaphragm relaxes gas flows from a region of lower pressure to a region of higher pressure the rib muscles and diaphragm contract, increasing the volume and decreasing the pressure within the lungs the rib muscles and diaphragm contract, increasing the volume and decreasing the pressure within the lungs A significant increase in the amount of interstitial fluid surrounding the capillary beds of a human's lungs will cause ______. an increases the amount of oxygen moving from the lungs into the blood a decrease in the amount of oxygen moving from the lungs into the blood a decrease in the amount of work needed for effective ventilation of the lungs an increase in the amount of carbon dioxide moving from the blood to the lungs an increase of pressure that would cause the capillary beds to burst a decrease in the amount of oxygen moving from the lungs into the blood Birds generate a lot of heat, especially during flight. Yet the adipose tissue under their skin and the feathers atop their skin make it difficult to eliminate excess heat across the skin. Which of the following alternatives can absorb body heat and eliminate it from the bird most effectively? lymph in the lymphatic vessels air in the air sacs blood in the heart blood in the vessels urine in the bladder air in the air sacs