No, DNA doesn't directly make proteins. Instead, DNA acts as the blueprint, containing the instructions for protein synthesis. This process involves two key steps: transcription and translation.
The Process of Protein Synthesis
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Transcription: DNA's genetic information is first copied into a messenger RNA (mRNA) molecule. This mRNA molecule acts as an intermediary, carrying the genetic code from the DNA in the nucleus to the ribosomes in the cytoplasm. [Source: MedlinePlus Genetics - How genes direct the production of proteins; Nature Scitable - Translation: DNA to mRNA to Protein]
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Translation: The mRNA molecule then travels to the ribosomes, where the genetic code is "read" and used to assemble amino acids into a specific protein chain. The order of amino acids is determined by the sequence of codons (three-nucleotide sequences) on the mRNA. [Source: Nature Scitable - Ribosomes, Transcription, Translation; Nature Scitable - Translation: DNA to mRNA to Protein]
Think of DNA as a master recipe book in the kitchen (nucleus), the mRNA as a copy of a single recipe (taken to the ribosomes), and the ribosomes as the cooks assembling the dish (protein) according to that recipe. [Source: Genome.gov - Deoxyribonucleic Acid (DNA) Fact Sheet]
Only about 1% of DNA codes for proteins; the remaining 99% has other crucial functions, including regulating gene expression. [Source: MedlinePlus Genetics - What is noncoding DNA?]
Environmental factors can also influence protein production; changes in the DNA's accessibility can impact how much protein is made. [Source: CDC - Epigenetics, Health, and Disease]
In essence, DNA provides the instructions, but the actual construction of proteins happens through a multi-step process involving mRNA and ribosomes.
