What is the Centeral Dogma of Biology
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The central dogma of biology is the idea "one gene, one protein"
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In each cell DNA is replicated and then used to create a mRNA strand through transcription which then can be translated to make a unique protein.
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TRIPLET CODE:
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The triplet code is three base sequences in the mRNA strand (CODON) that can code for a specific amino acid
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There are 20 amino acids and 64 possible codons to code for them
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Each codon is VERY precise there is no vagueness in the code, only a specific code will code for a specific amino acid
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There are also stop codons as well and in the base sequence of the mRNA strand there is punctuation in the code which tells the ribosome when to begin and stop making each protein.
Genetic Code & Polysomes
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The genetic code diagram is universal and this means that the same codons code for the same amino acids in all living things.
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This unity suggests living things have a common evolutionary ancestor.
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POLYSOMES:
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Even in polysomes translation can still occur amongst many ribosomes which can all create the same protein from a single mRNA strand simultaneously.
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Translation Process
STEP 1: INITIATION:
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To begin the process of protein synthesis the ribosome must read the start (AUG) codon at its "R" site on the ribosome.
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After this process begins the tRNA molecule binds to the mRNA start codon
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tRNA contains an anticodon that is complementary to the mRNA codon allowing it to bond
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tRNA carries an amino acid to the ribosome and attaches to the "P" site on the ribosome.
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When this happens the "A" site on the ribosome is still available for new tRNA molecules to bind to
