In terms of generating a depolarizing or hyperpolarizing graded potential on a postsynaptic cell, what do you think will be the most important factor?

The type of ion channel opened will be the most important factor.

Explanation:

At certain occasions a given neurotransmitter can combine with a K+ chemically gated channel and at certain occasions the same neurotransmitter can combine with a Na+ chemically gated channel. Thus, the same neurotransmitter can produce depolarization if it opens the Na+ channel and a hyper-polarization if it opens the K+ channel.  

In these situations, the structural make-up and sensitivity of the postsynaptic cell really determines if the neurotransmitter will inhibit (depolarize) or excite (depolarize) the postsynaptic cell. It is more essential to know the kind of channel, which opens than the particular identity of the neurotransmitter.  

hi my name is ashlynn and im 15

these macromolecules could either be amino acids, proteins or nucleic acids. they are responsible for the chemical changes and reactions that affects largely the cell and its composition. take for instance the cytoplasm of the cell where these organelles are settled. these simple organelles are composed of macromolecules which ignites and catalyses different functions that enables cells, in macro-perspective in motion and metabolism. in intestines for example, metabolism happens and breaking down parts of a food to simpler compounds that are used and these nutrients delivered throughout the body and again broken down by into smaller components.