Test your knowledge of ion diffusion across the plasma membrane by placing the correct word(s) in each sentence. Then, click and drag the sentences to arrange them in a logical paragraph order. attract ion channels negative membrane potential positive integral membrane repel electrochemical gradient concentration channel gating Ion diffusion depends on the _____, which is the separation ion channels of electrical charge across the plasma membrane. To begin, ions diffuse across plasma membranes by passing through _____ formed by _____ proteins. Thus, in determining ion flux, both the concentration difference and the membrane potential, collectively known as the _____, must be considered. For example, most cells have a net _____ charge inside with respect to the outside, so there is an electrical force attracting _____ ions into the cell. Ion diffusion also depends on the _____ gradient that exists for that ion across the plasma membrane. Finally, ion flux across the plasma membrane can be altered by opening or closing ion channels, which is a process known as _____. Electrical charges of the same sign, both positive or both negative, _____ each other, while opposite charges _____.