Question

Examine the curve below which is a measurement of energy cost of flight in a 15 gram bird.

1) What is the minimum cost of transport in this bird? (make sure you include appropriate units in your answer)

2) If this bird has fat reserves of 2 grams, how many miles can it fly using only its fat reserves?

3) How many joules of heat (minimum) will it produce?

4) If the fat is triglycerides, then a reasonable chemical formula is C₅₁H₁₄₀O₆. Using only this fat, what will be the Respiratory Exchange Ratio (RER) of the bird when it is flying?

5) How many L of CO₂ will it produce during its flight? (hint – again, be careful about units!)

Speed (m/s)     VO₂ (mLO₂/g·h)

4.0000              2.3333

6.0000              1.8667

7.0000              1.6000

8.0000              1.4667

9.0000              1.4200

10.0000            1.4667

11.0000            1.6000

12.0000            1.8667

13.0000            2.3333

Potentially useful information:

1 mile = 1609m, 1 gram of H₂O = 1 ml H₂O

Energy content of fat is 39.3 kJ/gram and 2.0 L of O₂ is consumed per gram of fat metabolized.

Kinetic energy = ½ mv², work = F X D

gravitational potential energy = mgh,

g = 9.8 m/s²

RER= CO₂ produced per unit time/O₂ consumed per unit time

Efficiency= work out/energy in=25% for muscles

Answer 1