A ribosome is composed of which of the following?

A ribosome is fundamentally composed of ribosomal RNA (rRNA) and proteins. This structure is crucial for its function in the cell. Ribosomal RNA forms the core of the ribosome and is essential for its structural integrity. It also plays a key role in catalyzing the formation of peptide bonds between amino acids, which is a critical step in protein synthesis. The proteins associated with rRNA provide additional structural support and contribute to the ribosome's activity, helping to stabilize the rRNA and facilitate the translation process.

In cellular biology, the ribosome serves as the site of protein synthesis, translating the sequence of messenger RNA (mRNA) into a chain of amino acids. This process is integral to the expression of genes and the functioning of cells. Other options listed do not accurately describe the composition of ribosomes. For instance, while messenger RNA is crucial for delivering genetic information for protein synthesis, it is not a structural component of ribosomes. Similarly, transfer RNA (tRNA) plays a role in translating mRNA into amino acids but does not constitute the ribosome itself, and lipids are not involved in the ribosomal structure or function. Lastly, stating that ribosomes are made up of only proteins would omit the essential ribosomal