16: Osmotic Regulation and Urinary System Flashcards
Module 3, Lesson 5
____ is determined by how many moles of one or more substances are dissolved in a fluid.
Osmolarity
____ is the ability of a solution to change a cell’s volume by osmosis.
Tonicity
A cell in a(n) ____ solution will lose water to the environment.
Hypertonic
A cell in a(n) ____ solution will gain water and expand.
Hypotonic
A cell in a(n) ____ solution will not change in volume.
Isotonic
True or false:
Tonicity is a relative measure, not a property of the solution itelf.
True
Maintaining ____ requires the exchange of water and electrolytes between the intracellular/extracellular fluids and the environment.
Osmotic balance
List the five major ions in body fluids.
- Sodium
- Chloride
- Calcium
- Magnesium
- Potassium
True or false:
The levels of the five major ions fluctuate widely inside the body fluid.
False
They are maintained at nearly constant levels.
Animals that conform to their environment, such as marine invertebrates, are called…
Osmoconformers
Animals that regulate their internal osmolarity, such as most marine vertebrates, are called…
Osmoregulators
True or false:
All animals living in freshwater must be osmoregulators.
True
All terrestrial animals are…
Osmoregulators
____ is produced by normal cellular activity, particularly the breakdown of amino acids and nucleic acids.
Nitrogenous waste
List the three main types of nitrogenous waste.
- Ammonia
- Urea
- Uric acid
____ is water-soluble, extremely toxic, and produced by amino acid breakdown.
Ammonia
Aquatic animals are easily able to remove ____ through passive diffusion into the surrounding water.
Ammonia
Amphibians, cartilaginous fish, and mammals convert ammonia into…
Urea
Reptiles and birds convert ammonia into…
Uric acid
____ is a less toxic form of ammonia that is still water-soluble.
Urea
The conversion of ammonia to ____ occurs in the liver and requires a lot of water.
Urea
____ is the least toxic form of ammonia, but is not water-soluble.
Uric aci
____ can be excreted without losing a lot of water, but requires energy to produce.
Uric acid
____ are branched tubules within the body that are only open to the outside of the body.
Protonephridia