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How do prokaryotic ribosomes differ from eukaryotic ribosomes?

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Diagram of a DNA polynucleotide chain showing linked deoxyribose sugars, phosphate groups, and nitrogenous bases (adenine, guanine, cytosine, thymine), with an inset comparing ribose and uracil in RNA. — Nucleic acid A portion of the polynucleotide chain of deoxyribonucleic acid (DNA), with an inset showing the corresponding pentose sugar and pyrimidine base in ribonucleic acid (RNA).

Prokaryotic and eukaryotic ribosomes differ primarily in their composition, size, and assembly:

Composition: Prokaryotic ribosomes consist of approximately 40 percent protein and 60 percent ribosomal RNA (rRNA). In contrast, eukaryotic ribosomes are composed of roughly equal parts protein and rRNA.1
Subunit Size: Ribosomal subunits are categorized by their sedimentation rate in Svedberg units (S). Prokaryotes contain a small 30S subunit and a large 50S subunit. Eukaryotes possess larger subunits, designated as 40S (small) and 60S (large).12
Assembly: In eukaryotic cells, ribosomal subunits are synthesized within the nucleolus of the nucleus. Prokaryotes, which lack a defined nucleus, do not utilize a nucleolus for this process.12

While both types of ribosomes serve as the essential sites for protein synthesis, these structural distinctions reflect significant evolutionary differences between the two cell types.12