One of the main reasons why mammals may have been able to evolve so quickly during the present era is due to the extinction of the main predators in the previous era. true or false

False, I'd say. Mammals usually adapt based on environment. Now, I know predators are "apart" of the environment, but I don't think that'd be it. I'd bet more money on saying mammals evolve based on environment adaptation. Sorry if I didn't answer your question or if I didn't get my point across well.

is in the form atp or adenosine triphosphate

it has to be understood that the sea water contains a huge amount of sodium and chlorine ions and if they enter the cell of the atlantic cod fish, the cell will shrivel and the fish will die. to avoid such a condition, the fish uses active transport for the purpose of removing the ions against the gradient.

explanation:

the atlantic cod is not a maritime osmoconformer. its native application of salts is less than that of the seawater it lives in. it is continually falling water from the gills to the ocean via osmosis.

countering that, the fish is going to be swallowing seawater. but since its internal collection of salts is lower than seawater, the fish will want to go free of excess salt, and since that's going upon a gradient, then active transport, requiring energy, must be used to pump out the salt. much marine fish use the organs to filter out the salt and these fish discharge very straight urine.