3. FUNCTIONS OF RNA 1. Messenger (mRNA) is made during TRANSCRIPTION a. a.Copies DNA into complementary codons (codon = sequence of 3 nucleotides) b. b.RNA polymerase enzyme binds to & begins with “AUG” Start Codon & ends at a “stop” Codon. c. c.Each codon directs a specific amino acid to be used to build an amino acid chain = protein. d. Moves information from the nucleus to the ribosomes in cytoplasm.

4. A - T T - A G - C C - G G - C C - G T - A UACGCCCGAUACGCCCGA DNA STRAND Separates A T T A G C C G G C C G T A RNA STRAND WRITTEN Thymine replaced with Uracil CODON

5. Leaves the nucleus Enters cytoplasm Binds to a ribosome Nucleus m

6. 2. Transfer RNA (tRNA) is used in TRANSLATION a. a. Process of converting the info in mRNA into a sequence of amino acids that make up a protein. b. b. tRNA molecule recognizes and brings only the specific amino acid (bonded to its top) to the mRNA. c. At the bottom of a tRNA molecule are three bases (an anticodon) which pair up with mRNA codons during translation allowing the release of the amino acid to a growing chain.

7. tRNA Molecule Has complementary Nucleotides to = mRNA’s codon

8. Anticodon Amino Acid tRNA Molecule mRNA Codon

9. mRNA Codon = Anticodon = Amino acid = DNA Codon = TTG RNA CODON CHART AAC UUG Asparagine

10. mRNA Codon = Anticodon = Amino acid = Does RNA have Thymine? DNA CODONCHART DNA Codon = TTG AAC UUG Asparagine

11. 3. Ribosomal RNA (rRNA) a. a.Site where mRNA is translated into an amino acid to build a protein (ribosome) b. b.Made of one big part and one small part. c. c.Small part has a groove that is a docking station for tRNA’s anticodons. d. d.tRNA’s anticodons line up with mRNA’s codons and then the amino acid is “unlocked” to attach to the growing chain.

12. Review….. n n Replication – (in nucleus)DNA copies itself before cell division so EACH cell has identical instructions (blueprints) n n Transcription – (in nucleus) makes the mRNAcodons from DNA which describe specific order of amino acids needed to build a protein. n n Translation – (in cytoplasm)“reads” the mRNA description (codons) & releases amino acids in correct order to make a protein - which makes a trait (hair color, shoe size, metabolism)