Yeah yeah so :D,
Large polar molecules can only cross the membrane with the help of protein named channel protein and carrier protein.
So, this both proteins act like a gate, the large molecules enter the protein and the protein let the large molecules in to the membrane. (see the picture so that you can understand more, its carrier protein)
the only difference between channel protein and carrier protein is, channel proteins has fixed shape while carrier protein can flip.
Answer:
Ans: Central Nervous System
Africa, australia, north america, south america, antarctica, asia, and europe
Adult Atlantic Salmon<span> live in coastal seas and </span>feed<span> on pelagic invertebrates ... The Atlantic </span>Salmon<span> is an iconic species in the north Atlantic </span>Ocean<span> and ... Unlike the pacific </span>salmons<span> (such as the Chinook</span>Salmon<span> [link]), Atlantic </span>Salmon do<span> not die after ... subpopulations that spawn in those rivers will almost certainly </span>go<span> extinct.</span>