1. RNA AND PROTEIN SYNTHESIS
SECTION 12-3
RNA AND PROTEIN SYNTHESIS

2. RNA STRUCTURE SINGLE STRAND MADE OF A LONG CHAIN OF NUCLEOTIDES
RNA NUCLEOTIDE IS MADE OF A NITROGEN BASE, A PHOSPHATE GROUP AND THE 5 CARBON SUGAR, RIBOSE

3. 3 WAYS THAT RNA DIFFERS FROM DNA
5-CARBON SUGAR IS RIBOSE
SINGLE-STRAND
CONTAINS THE NITROGEN BASE URACIL INSTEAD OF THYMINE
(A PAIRS WITH U)
4 NITROGEN BASES ARE ADENINE, URACIL, CYTOSINE & GUANINE

4. TYPES OF RNA MESSENGER RNA mRNA TRANSFER RNA (tRNA)
RIBOSOMAL RNA (rRNA)
MESSENGER RNA – READS, COPIES AND CARRIES THE INFORMATION IN DNA
TRANSFER RNA – TRANSFERS EACH AMINO ACID TO THE RIBOSOME AS SPECIFIED BY MESSENGER RNA

5. RNA RIBOSOMAL RNA – PART OF THE STRUCTURE OF THE RIBOSOME
RIBOSOMES ARE THE SITE OF PROTEIN SYNTHESIS

6. TRANSCRIPTION OCCURS IN THE NUCLEUS M RNA READS & COPIES INFO IN DNA;
RNA POLYMERASE IS THE ENZYME USED IN TRANSCRIPTION
OCCURS VERY QUICKLY – PROCEEDS AT A RATE OF 60 NUCLEOTIDES PER SECOND.

7. TRANSCRIPTION
RNA POLYMERASE BINDS TO DNA AT A PROMOTER-A SPECIFIC SEQUENCE OF DNA THAT ACTS AS A START SIGNAL FOR TRANSCRIPTION
RNA POLYMERASE SEPARATES THE DNA STRANDS
USING ONE STRAND OF DNA AS A TEMPLATE TO ASSEMBLE RNA NUCLEOTIDES INTO A STRAND OF MESSENGER RNA

8. TRANSCRIPTION ENDS WHEN A TERMINATOR IS REACHED
THE NEW STRAND OF MESSENGER RNA LEAVES THE NUCLEUS AND MOVES TO THE CYTOPLASM
THE DNA MOLECULE REASSEMBLES ITSELF INTO THE DOUBLE HELIX

9. TRANSLATION STEP 2 OF PROTEIN SYNTHESIS
DURING TRANSLATION, THE INFORMATION IN MESSENGER RNA IS TRANSLATED INTO A PROTEIN BY USE OF THE GENETIC CODE.

10. THE GENETIC CODE THE LANGUAGE OF MESSENGER RNA INSTRUCTIONS
CONTAINS THE AMINO ACIDS AND START AND STOP SIGNALS, OR CODONS, THAT ARE CODED FOR BY MESSENGER RNA.

11. MESSENGER RNA & THE GENETIC CODE
MESSENGER RNA CONTAINS CODONS WHICH ARE THE THREE-BASE SEQUENCES ONLY IN MESSENGER RNA.
THERE ARE 64 POSSIBLE THREE BASE CODONS.

12. VOCABULARY – GENETIC CODE
THE GENETIC CODE CONTAINS START AND STOP CODONS.
START CODON – AUG; TELLS TRANSLATION TO START
STOP CODON – UAA, UAG, UGA; TELLS TRANSLATION TO STOP

15. TRANSLATION TAKES PLACE IN THE CYTOPLASM ON THE RIBOSOME
IS THE DECODING OF A MESSENGER RNA INTO A POLYPEPTIDE CHAIN

16. TRANSLATION
BEGINS WHEN A MESSENGER RNA MOLECULE ATTACHES TO THE RIBOSOME
AS EACH CODON OF M-RNA MOVES THROUGH THE RIBOSOME,THE CORRECT AMINO ACID IS ATTACHED TO THE GROWING POLYPEPTIDE CHAIN BY T-RNA

17. TRANSLATION
TRANSFER RNA CARRIES THE ANTICODON-THE 3-BASE SEQUENCE THAT IS COMPLEMENTARY TO THE M-RNA CODON
EXAMPLE: M-RNA – CUG; T-RNA IS GAC.
THE ANTI-CODON SPECIFIES A SPECIFIC AMINO ACID

18. TRANSLATION
CONTINUES UNTIL A STOP CODON IS REACHED ON THE M-RNA MOLECULE
NEWLY FORMED POLYPEPTIDE IS RELEASED INTO THE CYTOPLASM
POLYPEPTIDE = PROTEIN – A CHAIN OF AMINO ACIDS LINKED BY PEPTIDE BONDS.

19. TRANSLATION
THE RIBOSOMES AND TRANSFER RNA CAN BE USED IN THE MAKING OF ANOTHER PROTEIN;
THEY ARE RECYCLED.

20. NECESSARY VOCABULARY PROTEINS – CHAINS OF AMINO ACIDS
AMINO ACIDS – 20 DIFFERENT INDIVIDUAL UNITS THAT FORM PROTEINS
POLYPEPTIDE – LONG CHAINS OF PROTEINS
CODONS – 3 BASE SEQUENCE IN MESSENGER RNA THAT DETERMINES WHICH AMINO ACID IS ADDED TO THE POLYPEPTIDE

21. VOCABULARY
ANTI-CODON – 3 BASE SEQUENCE ON A TRANSFER RNA MOLECULE WHICH ARE COMPLEMENTARY TO ONE OF THE MESSENGER RNA CODONS.
START CODON – AUG; TELLS TRANSLATION TO START
STOP CODON – UAA, UAG, UGA; TELLS TRANSLATION TO STOP

22. GENES
CODED DNA INSTRUCTIONS THAT CONTROL THE PRODUCTION OF PROTEINS WITHIN THE CELL
MOST GENES CONTAIN LITTLE MORE THAN INSTRUCTIONS FOR ASSEMBLING PROTEINS