AnS 214 Review Session 3

Monday, 1/25, 4pm

Cheezy Quote of the Day:

“The early bird gets the worm, but the second mouse gets the cheese.”

Jon Hammond

A) Avian respiration.

1) What about a bird's flight necessitates such high efficiency in their respiratory physiology?

2) What evolutionary advantage may have promoted the preservation of air sacs in the bird?

3) List two additional factors that may account for efficiency of avian respiration.

4) Compared to mammals, denote differences found in avians with respect to the following:

Respiratory muscles:

Body cavity design:

“Voice box”:

5) List the 5 types of air sacs found in bird species. How many are present in total?

6) Unlike mammalian lungs, bird lungs are not ______, and ventilation occurs with the help of air sacs. When a bird inspires, fresh air enters the ______air sacs, and is pushed into the ______of the lungs. Because old and new air never mix, and lungs are always at maximum capacity, birds are much ______efficient at gas exchange. To further maximize the absorption of O2 into the blood stream, blood and air flow undergo a ______exchange system. Similar to mammals, bird keep their lungs from collapsing with a surfactant called ______.

7) Why are humans less susceptible to influenza than are birds?

B) Comparative respiration

Compare mammalian and avian respiratory systems by filling in the table below.

Mammals / Birds
Lung type
Order of air flow
# of respiratory cycles (insp. + exp.) needed to move 1 volume of air through lungs
Expiration is......
Amount of dead space
Gas exchange occurs in....
Exchange efficiency
Respiration rate
Tidal volume



B) Hemoglobin dissociation curves

1) Fill in the banks of the leftmost diagram.

2) Define “% saturation of hemoglobin”.

3) a. What is the % saturation of hemoglobin at pO2 100? Blood with this pO2 is most likely located at what tissue?

b. What is the % saturation of hemoglobin at pO2 40? Blood with this pO2 is most likely located at what tissue?

c. What accounts for the difference in % oxygen saturation of blood at these two organ levels?

4) In your own words describe what the center and right diagrams state about the dissociation of oxygen from hemoglobin as a function of

a. body temp

b. pH