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Protein Synthesis. Chapter 10. RNA. ribonucleic acid contains the sugar ribose, uses uracil instead of thymine is single stranded usually much shorter in length than DNA (about the length of one gene). RNA & Transcription.
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Protein Synthesis Chapter 10
RNA • ribonucleic acid • contains the sugar ribose, uses uracil instead of thymine • is single stranded • usually much shorter in length than DNA (about the length of one gene)
RNA & Transcription During transcription, RNA polymerase binds to DNA and separates the DNA strands. RNA polymerase then uses one strand of DNA as a template from which nucleotides are assembled.
RNA vs. DNA RNA DNA So why the big diff? Single-stranded molecule in most of its biological roles and has a much shorter chain of nucleotides. Containsribose Complementary nucleotide to adenine is uracil Double-stranded helix Contains deoxyribose Complementary nucleotide to adenine isthymine
How Genes Work • Genes are coded DNA instructions that control the production of proteins with in the cell. • The first thing that needs to happen is for DNA to be copied into RNA. (transcription) • Now the RNA contains the coded information for making proteins.
The many faces of RNA Vocab!! Yes!! Messenger RNA (mRNA): carries copies of instructions for assemble of amino acids into proteins from DNA to the rest of the cell Ribosomal RNA (rRNA): makes up the major part of the ribosome Transfer RNA (tRNA): transfers amino acids to ribosomes during protein synthesis
The Genetic Code mRNA has a “4” letter alphabet: A, U, C, G “words” (codes) are only 3 letters long each 3 letter “word” is called a codon
The Genetic Code • Start codon: AUG • mRNA: indicates where translation should begin • Stop codons: UAA, UAG, UGA • Signal for translation to end
The Genetic Code UCGCACGGU UCG-CAC-GGU Serine-Histidine-Glycine
Translation Definitely a definition. DNA replication RNA transcription mRNA translation polypeptide Decoding of a mRNA message into a polypeptide chain (amino acids) Takes place on the ribosomes.
Translation • mRNA has the codon • tRNA has the anticodon