Question

Q1) why do nerve cells have a typical elongated shape?

Q2) what effects the movement of water across the plasma membrane ?

Answer 1

Q1)neurons are shaped the way they are because it is the best way to make a lot of connections without exponentially increasing the volume of the cell. They can receive information and transmit information over long distances without covering a lot of area.

Q2)Osmosis is simply the diffusion of water across a membrane - again from high to low concentration. In order to move against the concentration gradient (from low to high concentration), particles must undergo active transport. ... Size is another factor that affects the movement of molecules across a semipermeable membrane.

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Hope this helps :)