passive transport involves movement of substances......
A) from areas of lower concentration areas of higher concentrations.
B)from areas of higher concentrations to areas of lower concentration
C) from areas which the concentration has reached a balance
D) from areas of differing concentrations with the use of cellular energy
http://en.wikipedia.org/wiki/Passive_transport
Passive transport is a process where substances move across a cell membrane without the need for cellular energy. It occurs down the concentration gradient, which is the difference in concentration of a substance between two areas.
Now, let's analyze each of the given options to determine the correct answer:
A) From areas of lower concentration to areas of higher concentrations: This option is incorrect because passive transport never moves substances from areas of lower concentration to areas of higher concentration. Such movement would require the input of energy, which is not characteristic of passive transport.
B) From areas of higher concentrations to areas of lower concentration: This option is correct. Passive transport involves the movement of substances across a cell membrane in the direction of lower concentration, as it tries to reach equilibrium or balance.
C) From areas where the concentration has reached a balance: This option is incorrect because passive transport is a process that occurs until equilibrium is reached, not when it has already been reached.
D) From areas of differing concentrations with the use of cellular energy: This option is incorrect. Unlike active transport, which requires cellular energy, passive transport does not require energy.
So, the correct answer is B) from areas of higher concentrations to areas of lower concentration.