Marine Vert.-- ppt 4 (Kidneys, Gills, and Osmoregulation)

Osmotic environment

relative concentration of solutes

Osmosis

diffusion through semi-permeable membrane due to differential concentrations

T/F Osmosis is the movement of water from an area of high concentration to low.

true

Osmoregulators

regulate their internal osmotic environment within a narrow range.

What fish is not an osmoregulator?

Hagfish

Where does free osmosis occur in most fish?

the gills

Do fish have to expend energy to osmoregulate?

yes

Freshwater fish are ____ to their envirnment.

hyperosmotic

saltwater fish are _____ to their environment.

hypoosmotic

How do freshwater fish osmoregulate?

-remove water

-actively take in ions

How do saltwater fish osmoregulate?

-retain water

-actively excrete ions

What do the kidneys do?

-filter blood

-remove waste, water and salt

what is found in the kidneys that takes out water from their blood?

glomeruli

Do freshwater fish produce dilute urine or concentrated urine?

dilute urine

Which type of fish will have more glomeruli in their kidneys?

freshwater fish

T/F Saltwater fish cannot produce urine that is hyperosmotic to blood so excess salts must be actively excreted at gills.

True