Substances<span> move in and </span>out of cells<span> by diffusion down a concentration gradient, through a partially permeable membrane. The efficiency of </span>movement of substances in and out<span> of a </span>cell<span> is determined by its volume to surface area ratio. ... Osmosis is a type of diffusion but refers only to the </span>movement<span> of water molecules.</span>
Answer:
Amino acids
Explanation:
The building blocks of proteins are amino acids.
The correct answer is: [D]: "nitrogen fixation" .
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Evaporation of water from the oceans.