Which component of the cell structure is responsible for synthesizing proteins?

Ribosomes are the essential components of the cell responsible for synthesizing proteins. They can be found either floating freely in the cytoplasm or attached to the endoplasmic reticulum. Ribosomes read the messenger RNA (mRNA) that is transcribed from DNA and use it as a template to assemble amino acids into polypeptide chains, thus creating proteins. This process, known as translation, is fundamental for cell function, growth, and reproduction.

While the endoplasmic reticulum plays a role in protein synthesis and processing, as it provides a site for ribosomes to create proteins, it is the ribosomes themselves that directly carry out the synthesis. The cell membrane is a structural barrier that regulates what enters and exits the cell, and lysosomes are involved in digestion and waste disposal within the cell, neither of which are directly involved in protein synthesis.