Bio 1500 Exam 5 Questions and Answers 100% Pass

Bio 1500 Exam 5 Questions and Answers 100% Pass explain how the bird respiratory system differs from that of mammals - - parabronchi: site of gas exchange (comparable to our alveoli); fixed shape -air sacs: store fresh and used air -lungs: gas-exchange surface in the bird respiratory system (where does oxygen enter the blood and carbon dioxide leave the blood) Bird lungs don't expand/contract like mammal lungs, exchange of o2 happens in microscopic sacs Air flow in parabronchi in 1 direction only *Atmospheric pO2 in lung* 2100% Pass Guarantee Sophia Bennett, All Rights Reserved © 2025 explain the function of the air sacs and how the airflow in birds directs oxygen-rich air through the lungs at all stages of respiration - they store air for short periods, enabling fresh air to flow through the lungs during exhalation airflow into the parabronchi (gas exchange site) flows in only ONE direction ---> O2 and co2 never mix explain the advantage of unidirectional airflow - there is less mixing of fresh and 'used' air explain why the high efficiency respiratory system of birds does not work sufficiently well at high altitude - bar-headed geese have an amino acid structure that is better for high altitudes interpret the O2-Hb dissociation curves of normal (low altitude) and high-altitude birds(e.g bar-headed geese)with respect to the PO2available to them. - Bar headed: look this up Greylag goose have - proline Bar headed geese have - alanine Advantage of alanine over proline? - Alanine is a smaller AA, results in a gap which makes the structure looser and facilitates o2 binding 3100% Pass Guarantee Sophia Bennett, All Rights Reserved © 2025 -Substituting alanine for proline changes the quaternary structure, shifting its o2 dissoc. curve to the left (higher affinity for o2) Air flow in birds - (inhale) trachea --> posterior/rear air sacs --> parabronchi --> anterior/front air sacs --> trachea --> leaves the body There is fresh air in parabronchi in both inhalation and exhalation function of myoglobin in the body - stores O2 in slow/end