What produces proteins that control body processes?

• A. Genes
• B. Ribosomes
• C. Enzymes
• D. Chloroplasts

Answer: (A)

Genetic information carried by genes provides the instructions to make the proteins that regulate body processes. The cell reads these instructions through gene expression: DNA is transcribed into messenger RNA, and the ribosome uses that mRNA to assemble the correct sequence of amino acids into a protein. The specific protein built from a gene can act as an enzyme, hormone, receptor, or structural component, all of which influence metabolism, signaling, and overall physiology. The ribosome is the machine that actually builds the protein, but it follows the blueprint encoded by the genes. Chloroplasts can make some proteins in plant cells, but they aren’t the general source of proteins that control body processes. Enzymes are examples of such proteins, but they are products of gene expression, not the source of the instructions themselves.