DNA, mRNA, and Protein Synthesis

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DNA, mRNA, and Protein Synthesis

• TAKS Review for April 22 test

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What is DNA?

• DNA stands for Deoxyribonucleic acid
• Functions
• Store and transmit genetic info
• Contains the blueprint for making proteins

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Location and Structure of DNA

• Location
• Nucleus
• Structure
• Double stranded, often called double helix
• Composed of three part nucleotides
• Deoxyribose (sugar)
• Phosphate (PO4)
• Nitrogen base (1 of 4)
• Adenine (A)
• Thymine (T)
• Cytosine (C)
• Guanine (G)

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Base Pairing Rule
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DNA Replication

• During cell reproduction an exact copy of the
  parent cell is made
• DNA unzips to make two new strands of DNA
• Location Nucleus

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DNA Replication
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Making Proteins

• DNA contains the instructions for building
  proteins
• Proteins are made at the ribosomes
• DNA cannot leave the nucleus
• How does DNAs information get to the ribosome?

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Messenger RNA (mRNA)

• What is mRNA?
• Ribonucleic acid
• Single stranded
• Nucleotides composed of
• Ribose (sugar)
• Phosphate
• Nitrogen bases
• Adenine (A)
• Guanine (G)
• Cytosine (C)
• Uracil (U)

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How does mRNA take DNAs information to the
ribosome?

• Transcription RNA is made from a strand of DNA
• Location
• nucleus
• mRNA leaves the nucleus and takes the information
  to the RIBOSOME where a protein will be made

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Transcription
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What happens to mRNA at the ribosome?

• mRNA will bind to the ribosome
• tRNA will read mRNA in three part sections
  (codon)
• tRNA carries amino acids to the ribosome
• Amino acids will bond to form a protein

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Translation
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Genetic Code-language of mRNA

• Remember mRNA is read in 3 part sequences called
  a codon (64 total)
• Every 3 part sequence codes for an amino acid
• Proteins are determined by the order in which
  amino acids are joined together
• There are 20 different amino acids which can
  combine to form many different proteins