Hand in W.S. 10.1 before the bell rings

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Class Topics
Title Biology 3/22/07
Objectives

• To learn about how proteins are formed and the
  central dogma of biology.

• Hand in W.S. 10.1 before the bell rings
• Chapter 10 notes
• RNA review
• Protein synthesis
• Let the farmer forevermore be honored in his
  calling for they who labor in the earth are the
  chosen people of God.
• Thomas Jefferson
• National Agriculture Week 2007

Sunday, April 12, 2015 837 PM
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Class Assignments
By When
What

• Read 208-214 3/22/07
• W.S. 10.1 3/22/07
• W.S. 10.1 (SS/DL) 4/2/07
• Chapter 10 Quiz 1 4/4/07
• Due this class period
• Due next class period
• Due in the future

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Grade Sheet
2A p. 157 (5 pts.)
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RNA

• Ribonucleic Acid
• Carries out the instructions coded for by DNA
• Differences between RNA and DNA
• Ribose is the sugar
• Single stranded
• Uracil - not thymine - bonds with Adenine

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Types of RNA

• Messenger RNA
• mRNA takes DNA instructions to ribosomes
• Transfer RNA
• tRNA brings amino acids to ribosomes
• Ribosomal RNA
• rRNA makes up a part of each ribosome

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Protein Synthesis

• Proteins are manufactured on ribosomes
• Proteins are made from polypeptides
• Polypeptides are made from the 20 amino acids
  (monomer of protein)
• The order and number of amino acids determines
  the proteins properties
• DNA determines the order of amino acids because
  its the template

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Genetic Code

• Language of instructions for DNA and RNA
• Only 4 letters (ACTG)- yet 20 amino acids
• Is it read in groups of 1, 2, 3, or 4?
• 41
• 42
• 43
• 44

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(No Transcript)
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Codons

• DNA is read in groups of 3 nucleotides - called a
  codon
• Each codon represents an amino acid
• AUGGGGUUUCACACUUGGUGA

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Protein synthesis (Steps)Transcription

• 1. RNA polymerase attaches to DNA
• 2. RNA pol. causes DNA to separate into 2
  strands (unzip a short length)
• 3. DNA makes mRNA (transcription)
• mRNA complementary bases attach to DNA
• 4. mRNA leaves nucleus - through nuclear pores

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Protein synthesisTranslation

• 5. mRNA travels down ER to area of ribosomes (or
  out to free-floating ribosomes)
• 6. Ribosome (rRNA and protein) moves along mRNA
  translating the message
• 7. tRNA brings appropriate amino acid to mRNA (at
  ribosome) - peptide bonds formed between amino
  acids
• Appropriate amino acid determined by codon

Virtual Cell Animation
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Protein synthesis

• 8. tRNA leaves amino acid
• 9. Protein released
• 10. mRNA breaks apart
• Central Dogma

From http//esg-www.mit.edu8001/ esgbio/dogma/d
ogma.html
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Peptide bonds