1) The molecule pictured below is the segment of a longer molecule.
 

a) What kind of molecule is this?
 

b) What kind of enzyme would hydrolyze this molecule?
 

c) On the molecule, draw what the effect of this hydrolytic enzyme would be.
 

d) How are the breakdown products of this molecule absorbed into the intestinal epithelial cells?
 

2)  Welcome to the dog track!  The greyhound that you have bet on is a lean dog (no body fat), weighing 25kg.  While sprinting along the track, the dog is undergoing only aerobic metabolism and his VO2’  is 2 liters O2 • kg-1 • hr-1.  The only energy stores that the dog uses during the race are 200g of muscle and liver glycogen.  If the dog is running at 48 km • hr-1, how for can he run?

What is his cost of locomotion?
 

3) Describe the physiological, thermoregulatory responses of a terrestrial mammal to a decrease in temperature below its thermoneutral zone.

Why is it more difficult for an aquatic mammal to undergo such thermoregulation?

Why is it even more difficult for a fish to maintain a core temperature higher than that of the water?
 

4) What are two major roles for ATP during the contraction/relaxation cycle of vertebrate skeletal muscle?

The gastrocnemius muscle of a sprinter has high levels of glycogen stores.  That of a marathon runner has high levels of lipid stores.  Why is this and what are the advantages conferred to each?

revised 02 November 2000

roer@uncwil.edu