The correct answer is option (D) The active transport and the facilitated diffusion both involve the proteins present in the cell membrane.
Facilitated diffusion transport the large and the charged molecules through the protein transport channels present in the cell membrane. In this case, the solute move from a region of higher concentration to lower concentration and it does not require energy.
Active transports takes place when the molecules move from a region of lower concentration to higher concentration via the membrane protein channels.
Both facilitated diffusion and active transport requires the proteins present in the cell membrane.
I am confident that the answer should be.....<span>A protein acts as a pump and moves calcium ions from an area of low concentration to an area of high concentration.
Hope this helps.
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fertility problems is the right answer :)