DNA, RNA,

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DNA, RNA, and Proteins
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DNA and Protein Synthesis

• DNA contains the genetic information to
• make amino acids
• Amino acids combine to make proteins
• These proteins determine the physical traits
• of an organism and control cellular functions.
• Proteins do everything,
• and DNA gets all the
• credit!
• Think of them as tiny minions
• who do all the work

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DNA and Protein Synthesis
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DNA and Protein Synthesis

• Codon three bases code for a specific protein
• ex AAA Lysine
• The codons code for 20 amino acids
• Just like the alphabet has 26 letters to make
  all
• the words we know, the 20 amino acids make
• all the different proteins found in living
• organisms
• The codons are the template for protein
  synthesis,
• which takes place on the ribosomes (rRNA) in
  the
• cytoplasm

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DNA and Protein Synthesis Codons and amino
acids
Name the Amino Acid UAU CCG AGU
GCA
Tyrosine Proline Serine Alanine
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DNA and Protein Synthesis
But How does the information get from the DNA to
the cytoplasm?
mRNA
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DNA and Protein Synthesis - Transcription

• Transcription
• 1) DNA unzips
• 2) mRNA (messenger ribonucleic acid) copies info
  from DNA using base pairings
• RNA is different from DNA
• Single stranded, not double stranded
• Instead of deoxyribose, it has ribose
• instead of Thymine, it uses Uracil
• 3) Carries the genetic code from the nucleus to
  the
• ribosome in the cytoplasm

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DNA and Protein Synthesis - Translation

• Translation
• rRNA (ribosomal RNA) attaches to mRNA and starts
  reading the codons
• tRNA (transfer RNA) carries amino acids and
  attaches them to the growing protein chain
• When protein production is complete, the ribosome
  releases the protein chain

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DNA and Protein Synthesis - Summary
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DNA and Protein Synthesis
Practice making mRNA using the DNA template
DNA G A T T A C A
C U A A U G U mRNA
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DNA and Protein Synthesis

• Amino acids are linked together in the same
• order as the codons , creating a protein chain
• Just like linking letters to make words,
  linking
• amino acids makes proteins

mRNA CUA AUG UGC
Amino Acid
Amino Acid
Amino Acid
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DNA and Mutations

• Mutations are any changes that take place in DNA
  
• Can be spontaneous or caused by mutagens
• ex Chemicals, high temperatures, UV light,
• radiation
• Can change the genetic code, and be replicated
  
• when forming new body cells.
• In sex cells, can be passed on to offspring.
• Mutations can be neutral, beneficial, or
  harmful
• ex Blue eyes a mutation that occurred
  6-10,000 years ago, can be traced back to one
  ancestor
• what kind of mutation is that?

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DNA and Mutations Lets looks at different
mutations
THE DOG BIT THE CAT
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DNA and Mutations - Substitution

• THE DOG BIT THE CAT
• Substitution - Replace just one letter
• THE DOG BIT THE CAR

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DNA and Mutations - Deletion

• THE DOG BIT THE CAT
• Deletion Delete just one letter (T)
• THE DOG BIT HEC AT

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DNA and Mutations-Insertions

• THE DOG BIT THE CAT
• Insertion - Add just one letter (E)
• THE DOE GBI TTH ECA T
• Cells have proof reading proteins that
  constantly check the DNA and fix errors, so most
  are corrected

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Protein Synthesis- you try it!
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DNA transcription and translation- you try it!