"In the ocean, these Na+-Cl- ATPase molecules 'pump' Na+ and Cl- out of the salmon's blood into the salt water flowing over the gills, thereby causing NaCl to be lost to the water and offsetting the continuous influx of NaCl. In fresh water, these same Na+-Cl- ATPase molecules 'pump' Na+ and Cl- out of the water flowing over the gills and into the salmon's blood"
lol, so the salmon "breathes" salt in addition to oxygen?
ndr42•8mo ago
The difference is that the intake of oxygen is through diffusion (passive, along the concentration gradient) and the transport of Na+/Cl- uses ATP (active transport against the concentration gradient).
(The gills have the largest surface area to exchange ions and molecules.)
Edit: Spelling
dvh•8mo ago
I was surprised to learn that Nase and Vimba bream also lives in the sea. I live 400km from nearest sea and they are common here and form permanent freshwater populations here.
k__•8mo ago
lol, so the salmon "breathes" salt in addition to oxygen?
ndr42•8mo ago
(The gills have the largest surface area to exchange ions and molecules.)
Edit: Spelling