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Protein synthesis is the process by which the body creates proteins.
Explains protein synthesis, covering transcription in the nucleus and translation in the cytoplasm to assemble proteins from amino acids.
Key Takeaways
- Protein synthesis involves two main stages: transcription and translation.
- Transcription creates mRNA from DNA in the nucleus.
- Translation assembles amino acids into proteins using mRNA and tRNA in the cytoplasm.
- RNA polymerase and ribosomes are key enzymes in the process.
- The genetic code is translated accurately through codon-anticodon pairing.
Summary
- Protein synthesis is the process of creating proteins from amino acids within cells.
- Transcription occurs in the nucleus, converting DNA instructions into messenger RNA (mRNA).
- DNA base pairs include adenine-thymine and cytosine-guanine; uracil replaces thymine in mRNA.
- RNA polymerase reads DNA base triplets to build mRNA codons.
- Introns are removed and exons spliced together to form functional mRNA.
- mRNA leaves the nucleus and attaches to ribosomes in the cytoplasm for translation.
- Translation uses mRNA codons to match transfer RNA (tRNA) anticodons carrying specific amino acids.
- The ribosome assembles amino acids into a protein until a stop codon signals completion.
- The finished protein detaches from the ribosome, which then dissociates from the mRNA.
- The process ensures accurate protein assembly based on genetic instructions.
Full Transcript — Download SRT & Markdown
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Proteins consist of chains of amino acids, which amino acids used and their sequence determines each particular protein.
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The assembly of amino acids into proteins takes place in cells.
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The first stage, transcription, occurs in the nucleus.
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The second stage, translation, occurs in the cytoplasm.
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Transcription is the process of converting instructions for assembling a protein,
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located in the cell's DNA into messenger RNA. The template for building messenger RNA is a genetic sequence along a section of the DNA strand.
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Each strand of DNA contains nucleotides.
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with complementary bases.
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Adenine pairs with thymine and cytosine with guanine.
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Guanine.
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To start transcription, an enzyme called RNA polymerase attaches to the beginning of the DNA template.
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A sequence of three DNA bases called a base triplet contains information for assembling each amino acid of a protein.
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RNA polymerase reads the base triplets to build messenger RNA using free nucleotides.
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nucleotides.
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Corresponding messenger RNA triplets are called codons. In mRNA codons, uracil replaces thymine.
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thymine.
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Once the mRNA is built, certain enzymes remove introns, or sections that will not be used to build the protein. Enzymes splice the remaining ends or exons together.
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Then the functional mRNA leaves the nucleus.
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Translation is the process of using messenger RNA to assemble amino acids into a protein.
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The structure that will read the mRNA, called a ribosome,
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attaches to the mRNA strand.
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Initiated by a start codon, the ribosome reads each subsequent codon,
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which signals a transfer RNA molecule that has the matching anticodon sequence
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and specific amino acid.
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The process continues as additional transfer RNA molecules attach,
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bringing the correct amino acids to build the protein until the protein
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is completely assembled, signaled by the stop codon.
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codon.
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After the assembled protein breaks away from the ribosome,
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its subunits detach from the mRNA.
Topics:protein synthesistranscriptiontranslationDNAmRNARNA polymeraseribosomeamino acidsgenetic codetRNA
