Genes are fundamental blueprints used by cells to construct proteins. The process of how genes are used to build proteins involves multiple steps where DNA is transcribed and translated.
Here’s a breakdown of the process:
The Central Dogma: DNA to Protein
The central dogma of molecular biology describes the flow of genetic information within a biological system. It outlines how information in DNA is used to create functional products, namely proteins.
| Step | Molecule Involved | Description |
|---|---|---|
| Transcription | DNA, RNA | Genes in DNA serve as templates to synthesize RNA molecules. |
| Translation | RNA, Ribosomes | The RNA molecule is then used to direct the assembly of amino acids into a protein. |
Detailed Explanation
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Transcription: The process starts with transcription. During transcription, the information encoded in DNA is copied into a complementary RNA molecule called messenger RNA (mRNA). RNA polymerase, an enzyme, binds to the DNA and synthesizes the mRNA using the DNA sequence as a template.
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Translation: The mRNA molecule carries the genetic code from the nucleus to the ribosomes in the cytoplasm. At the ribosome, the mRNA is translated into a specific sequence of amino acids. Transfer RNA (tRNA) molecules, each carrying a specific amino acid, recognize and bind to corresponding codons (three-nucleotide sequences) on the mRNA. The amino acids are then linked together to form a polypeptide chain, which folds into a functional protein.
Key Points from the Reference
According to the Quizlet flashcards:
- "The genes in DNA direct the synthesis of an RNA molecule, which is used to build a protein."
- "DNA is transcribed into an amino acid sequence."
These statements highlight the two main steps in protein synthesis: transcription (DNA to RNA) and translation (RNA to protein, which ultimately determines the amino acid sequence).
