Examination of a cell by transmission electron microscopy reveals a high density of ribosomes in the cytoplasm. this observation suggests that this cell is actively producing large amounts of which of the following molecules?

Proteins.

Explanation:

Ribosomes are cellular organelles, the protein builders the cell. They link amino acids together in the order specified by the genetic material, so the result is a long chain of amino acids that form a protein. Free ribosomes  found in the cytoplasm are important because they produce proteins which are essential for internal cellular activity.

The advantage of having a high density of ribosomes working at the same time is speed, as proteins are made one after another. Then, the more ribosomes there are, the more proteins there will be.

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