44.2 forms of nitrogenous waste Flashcards
1
Q
wastes that vary in toxicity and energy costs of producing them
A
ammonia
urea
uric acid
2
Q
What is needed for ammonia excretion
A
water becuae it can only be tolerated in small concentrations
3
Q
how does ammonia get excreted?
A
- its highly soluble so it diffuses straight through the membrane
- fishes: gills or in minor amounts through the kidneys
- invertebrates; across entire body
4
Q
most mammals, adult amphibians, sharks, and turtles excrete
A
urea
5
Q
urea
A
- produced in the liver
- combines ammonia with carbon dioxide
6
Q
pros and cons or urea
A
pro: low toxicity, less water
con: energy cost
7
Q
insects, land snails, and reptiles, and birds excrete
A
uric acid
8
Q
uric acid
A
- nontoxic
- does not dissolve in water
- semisolid paste with little water
9
Q
pros and cons of uric acid
A
pro: little to no water
con: more energy than even urea
10
Q
uric acid in other animals
A
-all animals make it due to purine breakdown
11
Q
what happens when the uric acid is insoluble
A
- dalmatians form stones of uric acid in their bladder
- humans get gout: or uric acid crystals that inflame the joints
