BIO 370 - VERTEBRATE ZOOLOGY
EXAM 2 WITH COMPLETE SOLUTIONS
Freshwater fish are HYPERosmotic. What does this mean? - ANS ✔✔Freshwater fish GAIN water
and LOSE ions. (Na+, Cl-) This is done so that the fish maintains an osmolality similar to that of
its surroundings.
Seawater fish are HYPOosmotic. What does this mean? - ANS ✔✔Seawater fish LOSE water and
GAIN ions. This is done so that the fish maintains an osmolality similar to that of its
surroundings.
What portion of the fish is responsible for maintaining osmolality? - ANS ✔✔the Gills and
kidneys
Is it freshwater fish or seawater fish that actually drink water? - ANS ✔✔Seawater fish, this is
done to prevent dehydration
Do freshwater fish drink water? - ANS ✔✔No. They get too much water from osmosis already.
Many vertebrates are ECTOTHERMS. What does this mean? - ANS ✔✔They gain/lose heat from
outside
Some (aquatic mammals) are ENDOTHERMS. What does this mean? - ANS ✔✔They generate
and regulate heat internally.
Some ECTOTHERMS use REGIONAL HETEROTHERMY. What is this? - ANS ✔✔Different parts of
the body are at different temperatures. This is done by retaining heat produced by working
muscles.
, True or False: Billfish and mackerel use heater cells behind their eyes to induce regional
heterothermy (keep different parts of the body at different temperatures) - ANS ✔✔True
What is the problematic molecule that is a byproduct of protein and nucleic acid degradation? -
ANS ✔✔Ammonia (NH4)
What is the elimination of ammonia with water in aquatic animals called? - ANS
✔✔Ammonotely
What is the main waste product of mammals? - ANS ✔✔Urea
What is the excretion of urea called? - ANS ✔✔Ureotely
What is the main waste product of reptiles(including birds)? - ANS ✔✔Uric Acid
What is a benefit for mammals for excreting mostly urea instead of ammonia? - ANS ✔✔Urea
requires much less water than ammonia to eliminate
What is the elimination of uric acid called? - ANS ✔✔Uricotely
What main nitrogenous waste would you expect a tadpole (Hint: aquatic) to produce? - ANS
✔✔Ammonia
What main nitrogenous waste would you expect a frog (Hint: Terrestrial) to produce? - ANS
✔✔Urea
EXAM 2 WITH COMPLETE SOLUTIONS
Freshwater fish are HYPERosmotic. What does this mean? - ANS ✔✔Freshwater fish GAIN water
and LOSE ions. (Na+, Cl-) This is done so that the fish maintains an osmolality similar to that of
its surroundings.
Seawater fish are HYPOosmotic. What does this mean? - ANS ✔✔Seawater fish LOSE water and
GAIN ions. This is done so that the fish maintains an osmolality similar to that of its
surroundings.
What portion of the fish is responsible for maintaining osmolality? - ANS ✔✔the Gills and
kidneys
Is it freshwater fish or seawater fish that actually drink water? - ANS ✔✔Seawater fish, this is
done to prevent dehydration
Do freshwater fish drink water? - ANS ✔✔No. They get too much water from osmosis already.
Many vertebrates are ECTOTHERMS. What does this mean? - ANS ✔✔They gain/lose heat from
outside
Some (aquatic mammals) are ENDOTHERMS. What does this mean? - ANS ✔✔They generate
and regulate heat internally.
Some ECTOTHERMS use REGIONAL HETEROTHERMY. What is this? - ANS ✔✔Different parts of
the body are at different temperatures. This is done by retaining heat produced by working
muscles.
, True or False: Billfish and mackerel use heater cells behind their eyes to induce regional
heterothermy (keep different parts of the body at different temperatures) - ANS ✔✔True
What is the problematic molecule that is a byproduct of protein and nucleic acid degradation? -
ANS ✔✔Ammonia (NH4)
What is the elimination of ammonia with water in aquatic animals called? - ANS
✔✔Ammonotely
What is the main waste product of mammals? - ANS ✔✔Urea
What is the excretion of urea called? - ANS ✔✔Ureotely
What is the main waste product of reptiles(including birds)? - ANS ✔✔Uric Acid
What is a benefit for mammals for excreting mostly urea instead of ammonia? - ANS ✔✔Urea
requires much less water than ammonia to eliminate
What is the elimination of uric acid called? - ANS ✔✔Uricotely
What main nitrogenous waste would you expect a tadpole (Hint: aquatic) to produce? - ANS
✔✔Ammonia
What main nitrogenous waste would you expect a frog (Hint: Terrestrial) to produce? - ANS
✔✔Urea
