Cells need to bring in molecules to carry out cellular processes. Often, this requires moving the molecules across the cell membrane against the concentration gradient.
How do these molecules get into the cell?

Active transport

Explanation:

The text is most likely speaking about active transport, such as endocytosis and exocytosis, which is essentially the process in which a cell uses to consume larger particles/molecules and expose of them, respectively.

the three components of a nucleotide are the nitrogenous base, the phosphate group and the five-carbon sugar.

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