Transcription & Translation RNA & Proteins

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3 I) Why is RNA important to all living things?

4 I) RNA A) Stands for Ribonucleic acid B) Acts as a messenger for DNA, carrying the DNA code outside of the nucleus & into the cytoplasm where it can be worked on by ribosomes

5 II) What are the parts to a RNA molecule?

6 II) Characteristics A)1 main side (half of a ladder) B)The side is made of alternating sugars (ribose) & phosphate groups

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8 II) Characteristics C) The rungs of the ladder are nitrogenous bases 1)There are 4 bases: adenine (A), guanine (G), cytosine (C), & uracil (U) 2)A  U / T  A 3)G  C

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11 III) Where do RNA & proteins come from?

12 A) The Central Dogma 1) AKA: The Foundation of Modern Biology

13 You need to know this, this is the central dogma

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15 IV) RNA Types A)Messenger RNA 1)mRNA is made by the enzyme RNA polymerase 2)mRNA is edited some before it leaves the nucleus, 3)mRNA carries the DNA message from the nucleus to the ribosome (in the cytoplasm) 4)Codon is a three letter sequences on the mRNA RNA polymerase DNA RNA Adenine (DNA and RNA) Cystosine (DNA and RNA) Guanine(DNA and RNA) Thymine (DNA only) Uracil (RNA only)

16 IV) RNA Types B) Transfer RNA 1)tRNA carries the attached amino acids to the mRNA / ribosome unit in the cytoplasm 2)Anticodon is a three letter sequence on the tRNA that binds with codon on the mRNA

17 IV) RNA Types C) Ribosomal RNA 1)rRNA is the construction site for the protein & is what makes the ribosome

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19 V) Transcription A)RNA is copied from DNA using the enzyme RNA Polymerase B)Only the sense strand (one side of the DNA) is transcribed into RNA C)The antisense strand (other side of the DNA) is not transcribed D)Transcription occurs from the 5’ to 3’ end of new mRNA strand (sense strand is read 3’ to 5’ direction)

20 RNA Polymerase

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23 VI) Translation A)This is the process of making a protein from an RNA template B)This process uses mRNA, tRNA, rRNA, ribosomes, & amino acids C)Each tRNA anticodon carries with it a particular amino acid, and this pairs with the mRNA codon at the ribosome to add amino acids, one amino acid at a time

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25 Methionine Phenylalanine Ribosome mRNAStart Codon Lysine tRNA mRNA Nucleus

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31 VII) Protein A)Nutrients used to build & repair the body; they are made of amino acids B)Your body can make some amino acids; others must be obtained from your diet

32 General structure of amino acids Alanine Serine Amino Group Carboxyl Group Variable Side Chain

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34 Amino Acids Protein

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36 VIII) Genetic Code A)The original DNA message, in a mRNA delivery system form B)tRNA’s decoders used to decipher the message into proteins

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