a very simple biology question?

polarity, meaning how polar it is or non-polar it is. A polar molecule will have a pair of equal charges. A positive and a negative.

The more polar a substance is, meaning the more electronegative it's atoms are, the greater chance they have of catching other atoms, lowering the amount that pass though the plasma.

Confusing, I know. But try and think of it this way:

Molecules that are either non polar or slightly polar---> Less catchy, plasma cannot catch as much molecules.

Molecules that are very polar -----> More catchy, plasma can catch heaps of molecules.

These things are all related in that they are involved with moving things into and out of cells. I would do a specific search on each of the topics and read the long explanations. Homeostasis is a word that means keep everything the same. So anytime there is a change, homeostasis kicks in to get it back the way it was. It will take me at least an hour to answer all of these in a way that will make sense. I hope someone else can answer them faster. If not, try asking each of them separately.

Polarity refers to the molecules charge, negative or positive.

A polar bond is a covalent bond in which there is a separation of charge between one end and the other - in other words in which one end is slightly positive and the other slightly negative. Examples include most covalent bonds. The hydrogen-chlorine bond in HCl or the hydrogen-oxygen bonds in water are typical and are said to show polarity.