<span>"Carrier proteins bind to the substances they transport across the membrane via facilitated diffusion, whereas channel proteins provide a pore for substances to move across the membrane via facilitated diffusion."
This is the most correct option.
The main difference, when comparing these two gates of transportation across a membrane through the same process (via facilitated diffusion or any other), is that carrier proteins bind to the substances they transport and only communicate with one environment of the cell (whether intracellular or extracellular) at the time, while channel proteins let substances move across the membrane without any binding being opened to both cell environments.</span>
The crossing over mechanism of genetic variation results from the exchange of gene segments between non sister chromatids. The correct answer is A.
