The relative impermeability of membranes to water soluble molecules is a result of the .

Because the membrane is semi-permeable

or

The membrane selectively allows molecules that passes(smaller molecules) the pores of the membrane to pass through while those which have larger molecules does not pass through.

he is very short, and he can only reach halfway up on the elevator buttons. but on a rainy day, he has his umbrella with him, and he uses it to poke the button at the top.

bc blah

explanation:

bc blah