The greater the concentration gradient, the faster the rate of diffusion.
Identities are statements that are true for any number.
What are three statements that are true about Francis Drake?
Particles move through cell membranes w/out the use of energy by cells.
The greater the concentration gradient, the faster the rate of diffusion.
Statements that always or never hold true are called "tautologies."
Lots of statements about novels are true.
Lots of statements are not true about polymers.
Lots of statements about animals are true.
Lots of statements are not true about polymers.
Without know what statements you are referring to we cannot answer.
is it true or false that barriers to diffusion are mostly because of the local cultures?
That depends entirely on the statements in question.