LIFE 103 Final Exam Questions And Answers With Verified Study Solutions

___________ supplies o2 for cellular respiration and siposes CO2 - Answer-gas exchange _______ is the pressure exerted by a particular gas in a mixture of gases - Answer-Partial pressure T/F: Gases undergo net diffusion of higher partial pressure to a region of lower partial pressure - Answertrue Oxygen takes up ____ of air around us - Answer-21% T/F: Breathing air takes up a lot of energy for terrestrial animals - Answer-false, 30 times less oxygen present in water - water animals need to spend more energy to exchange gases Where does gas exhange occur - Answer-respiratory surfaces Gas echange across respiratory surfaces takes place by _____ - Answer-diffusion (movement of gas down its partial pressure gradient- does not occr quickly over long distances) - large in surface area and thin Earthwroms and frogs use _____ as a respiratory sruface - Answer-skin after it rains soil pockets fill with water, end up on concrete to breathe since they breathe through their skin - Answer-(fun fact) _____ are outfoldings of the body that create a large surface area for gas exhange - Answer-gills (lungs turned inside out) _______ moves the respiratory medium over the respiratory surface - Answer-Ventilation T/F: aquatic animals move thorugh water or move water over their gills for ventilation (by using mouth) - Answer-trueIf fish were to swim backwards, this would cause problems. why? - Answer-countercurrent exchange, water and blood moving opposite directions fish gills use a _________ system - Answer-countercurrent exhange water has higher partial pressure than oxygen in the blood - Answerblood is always less saturated with 02 than the water it meets - Answermaximizes efficiency of gas exhange - Answer-80 percent of available oxygen (humans max 25 percent) the _______ of insects consits of a network of branching tubes throughout the body - Answer-tracheal system tracheal tubes supple 02 _____ - Answer-directly to body cells the respiratory and circulatory systems are _____ in insects - Answer-separate, circulatory unneeded because air is in contact with most cells throughout organism ( you can only get so big) ______ are an infolding of the body surface - Answer-lungs in mammals, gas exhchange takes place in ______, air sacs at the tips of bronchioles - Answer-alveoli T/F: In birds, air passes in one direction only, making ventilation very inefficient - Answer-false, ventilation is highly efficient (two inhales and two exhales for full circuit, well ventilated furnace) (intake and exhaust is mixed in humans, doesn't occur with birds) why high altitude is chill mammals ventilate lungs by _________ pressure breathing, which pulls air into lungs - Answer-negative (like pulling a syring, suction)Lung volume increases as the diaphragm contracts - AnswerBlood arriving in the lungs has a low partial pressure of O2 and high partial pressure of CO2 (relative to air in the alveoli) - Answerin the alveoli, O2 diffuses into the blood and CO2 diffuses into the air - AnswerOsmoconformers are __________ with their surroundings and do not regulate with their osmolarity - Answer-isoosmotic Freshwaster animals constantly take in water by osmosis from their hypoosmotic environment - Answertrue lose salts by diffusion, maintain water balance by drinking almost no waer and excreting large amounts of dilute urine - Answerfragmentaion - Answer-breaking of the body into piees, some or all of which develop into adults Fragmentation must be accompanied by ______________. - Answer-regeneration (regrowth of lost body parts) Parthenogenesis: - Answer-development of a new individual from an unfertilized egg