What is the function of ribosomes in a cell?

• A. To package and transport proteins
• B. To synthesize proteins
• C. To modify lipids
• D. To store genetic information

Answer: (B)

Ribosomes play a crucial role in the process of protein synthesis within cells. They are composed of ribosomal RNA (rRNA) and proteins, and they can either be found floating freely in the cytoplasm or attached to the endoplasmic reticulum (forming rough ER). The main function of ribosomes is to translate messenger RNA (mRNA) into proteins, a process known as translation.

During translation, ribosomes read the sequence of mRNA, which is a copy of the genetic code from DNA, and assemble amino acids in the correct order to form a polypeptide or protein. This process is vital for all cellular functions, as proteins are necessary for structure, function, and regulation of the body's cells, tissues, and organs.

The incorrect options highlight other cellular functions but do not pertain to ribosomes. For example, packaging and transporting proteins is primarily carried out by the Golgi apparatus, while lipid modification is a function associated with smooth endoplasmic reticulum. Storing genetic information is the role of DNA found in the nucleus, rather than ribosomes. This highlights that while many structures within a cell contribute to overall cell function, ribosomes specifically are dedicated to synthesizing proteins.