How diffusion works?

Now, answer the quiz:

1	Simple diffusion is defined as the movement of
	A)	molecules from areas of higher concentration to areas of lower concentration.
	B)	molecules from areas of lower concentration to areas of higher concentration.
	C)	water molecules across a membrane.
	D)	gas molecules across a membrane.
	E)	gas or water molecules across a membrane.
2	When sugar is mixed with water, equilibrium is reached when
	A)	molecules of sugar stop moving.
	B)	water and sugar molecules are moving at the same speed.
	C)	the dissolved sugar molecules are evenly distributed throughout the solution.
	D)	there are the same number of water molecules as dissolved sugar molecules.
	E)	two tablespoons of coffee are added.
3	The rate of diffusion is affected by which of the following?
	A)	temperature
	B)	size of molecules
	C)	steepness of the concentration gradient
	D)	A and B
	E)	A, B and C
4	The molecules in a solid lump of sugar do not move.
	A)	True
	B)	False
5	Diffusion is one of the processes whereby materials are exchanged between a cell and its environment.
	A)	True
	B)	False

Answers:

1)

	A)  molecules from areas of higher concentration to areas of lower concentration.

2)

	C) the dissolved sugar molecules are evenly distributed throughout the solution.
3) E) A, B and C 4)  B) False 5) A) True