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RNA and Protein Synthesis. RNA (Ribonucleic Acid). Similar to DNA, except… Sugar is ribose Single stranded Uracil (U) instead of Thymine (T). Three types of RNA. Messenger RNA (mRNA) – carries copies of instructions for making proteins Ribosomal RNA ( rRNA ) – makes up ribosomes
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RNA (Ribonucleic Acid) • Similar to DNA, except… • Sugar is ribose • Single stranded • Uracil (U) instead of Thymine (T)
Three types of RNA • Messenger RNA (mRNA) – carries copies of instructions for making proteins • Ribosomal RNA (rRNA) – makes up ribosomes • Transfer RNA (tRNA) – transfers specific amino acids to the ribosome according to instructions.
Transcription • The process of copying part of the DNA molecule into a complimentary strand of mRNA. • Occurs in the nucleus • RNA polymerase (the enzyme) binds to DNA in the nucleus and separates the DNA into strands. • RNA polymerase then uses one strand of DNA as a template for making a strand of mRNA that is released into cytoplasm.
Codon • Three consecutive nucleotides that code for a particular amino acid. • Example: UAC AGU CCU GGA
Translation • The process of decoding the message in mRNA to produce a sequence of amino acids in a chain (protein). • Occurs in the cytoplasm • mRNA attaches to ribosome • Each codon allows the proper amino acid to be brought into the ribosome by tRNA. • Amino acids are attached together along the “assembly line” • This continues until a “stop”codon is reached.
