Balance
This is the regulation of water and ion balance in the body.
What is osmoregulation?
In this process, water diffuses across a selectively permeable membrane from low solute concentration to high solute concentration.
What is osmosis?
Excretory tubules are made of this type of tissue.
What is transport epithelium?
This nitrogenous waste is highly toxic and can only be excreted in dilute solutions.
What is ammonia?
Most marine invertebrates are this type, with body fluids that match seawater.
What are osmoconformers?
This is the control of body temperature.
What is thermoregulation?
The body fluids of humans and other mammals have an osmolarity of about this.
What is 300 mOsm/L?
This is the first step in tubule function.
What is filtration?
Mammals make this relatively nontoxic waste by combining ammonia with HCO₃⁻.
What is urea?
Seawater and the body fluids of marine invertebrates have an osmolarity of about this.
What is 1,000 mOsm/L?
This process gets rid of metabolic wastes while helping maintain water and ion balance.
What is excretion?
A solution with a higher osmolarity than the solution on the other side of a membrane is described this way.
What is hyperosmotic?
In this step, useful solutes and water are moved from the tubule back into the body fluids.
What is tubular reabsorption?
Birds, reptiles, and insects excrete this insoluble waste as a paste.
What is uric acid?
Insects and other arthropods excrete wastes through these tubules.
What are Malpighian tubules?
In complex animals, cells are surrounded by this aqueous fluid.
What is extracellular fluid (ECF)?
In these animals, the osmolarity of the cellular and extracellular fluids matches the environment.
What are osmoconformers?
In this selective step, specific small molecules and ions are moved from the ECF and blood into the tubule.
What is tubular secretion?
The type of nitrogenous waste an animal produces depends on a balance among these three factors.
What are toxicity, water conservation, and energy requirements?
Annelids and most adult mollusks excrete wastes through these tubules.
What are metanephridia?
In animals with a circulatory system, the ECF includes these two fluids.
What are interstitial fluid and blood plasma?
These animals use control mechanisms to keep their body fluids at an osmolarity that may differ from their surroundings.
What are osmoregulators?
This end of the tubule is immersed in body fluids, while the distal end opens to the outside of the body.
What is the proximal end?
Compared with excreting the same amount of nitrogen as ammonia, excreting uric acid saves about this percentage of the water.
What is 99%?
Flatworm protonephridia end in this cell, named because its beating cilia look like a flickering flame.
What is a flame cell?