Bio 1500 - exam 5
1. explain how the bird respiratory system differs from that of mammals: - bird
lungs are more complicated than mammal lungs
- gas exchange occurs in the parabronchi
- multiple air sacs to "store" fresh and used air
- unidirectional airflow
- little residual volume
- slow breathing rate
- thin diffusion distances in the lung
- larger lung surface area
2. 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: - inhalation: air goes
through the parabronchi into the posterior air sac while oxygen poor air from the lungs simultaneously moves into the
anterior air sacs
- exhalation: air moves from posterior air sacs into the lungs and passes through the lung tissues on the way so oxygen
can enter the bloodstream; air from anterior air sacs is exhaled
3. explain the advantage of unidirectional airflow: there is less mixing of fresh and 'used' air;
allows for consistent, controlled movement of air in a single direction, preventing turbulence and effectively removing
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, particles from a designated area
4. explain why the high efficiency respiratory system of birds does not work
sufficiently well at high altitude: flying requires a lot more energy and O2 compared to rest; the
bar-headed geese are better equipped for high altitudes because they have a mutation in their hemoglobin (alanine
is substituted for proline)
5. interpret the O2-Hb dissociation curves of normal (low altitude) and high-al-
able to them-
flnity, but it is lower
titude birds (e.g bar-headed geese) with respect to the PO2 avail
: bar-headed geese do not need higher PO2 for Hb saturation; the greylag geese have normal a
than bar-headed geese
6. what are the binding rules for DNA bases?: A binds with T and C binds with G
7. what is the first step of protein synthesis?: transcription
8. what is transcription?: the process of making mRNA from DNA in the nucleus in order to transport it to
the ribosome
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1. explain how the bird respiratory system differs from that of mammals: - bird
lungs are more complicated than mammal lungs
- gas exchange occurs in the parabronchi
- multiple air sacs to "store" fresh and used air
- unidirectional airflow
- little residual volume
- slow breathing rate
- thin diffusion distances in the lung
- larger lung surface area
2. 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: - inhalation: air goes
through the parabronchi into the posterior air sac while oxygen poor air from the lungs simultaneously moves into the
anterior air sacs
- exhalation: air moves from posterior air sacs into the lungs and passes through the lung tissues on the way so oxygen
can enter the bloodstream; air from anterior air sacs is exhaled
3. explain the advantage of unidirectional airflow: there is less mixing of fresh and 'used' air;
allows for consistent, controlled movement of air in a single direction, preventing turbulence and effectively removing
1/4
, particles from a designated area
4. explain why the high efficiency respiratory system of birds does not work
sufficiently well at high altitude: flying requires a lot more energy and O2 compared to rest; the
bar-headed geese are better equipped for high altitudes because they have a mutation in their hemoglobin (alanine
is substituted for proline)
5. interpret the O2-Hb dissociation curves of normal (low altitude) and high-al-
able to them-
flnity, but it is lower
titude birds (e.g bar-headed geese) with respect to the PO2 avail
: bar-headed geese do not need higher PO2 for Hb saturation; the greylag geese have normal a
than bar-headed geese
6. what are the binding rules for DNA bases?: A binds with T and C binds with G
7. what is the first step of protein synthesis?: transcription
8. what is transcription?: the process of making mRNA from DNA in the nucleus in order to transport it to
the ribosome
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