Quiz (take out a sheet of paper 1. T/F DNA can exit the nucleus 2. Name the bases found in RNA 3. Name the enzyme used to construct RNA during transcription 4. BONUS ► Create the matching RNA sequence for this DNA ► ATTGGTACA

Presentation outline ► Review of Central Dogma of Molecular Biology ► Codons and anticodons ► Overview of Translation  RNA  protein ► Mistakes in DNA

Purpose of DNA ► DNA holds the genetic information.  A blueprint for the cell  It tells the cell what to build ► The purpose of DNA  DNA codes for the proteins that make up an organism ► The past two days we talked about DNA replication and transcription (DNA to RNA) ► Today, we talk about translation (RNA to protein)

Central Dogma of Molecular Biology 1. DNA 2. RNA 3. Protein

RNA DNA RNA polymerase Figure 12–14 Transcription Section 12-3 Adenine (DNA and RNA) Cystosine (DNA and RNA) Guanine(DNA and RNA) Thymine (DNA only) Uracil (RNA only) Go to Section:

Purpose of translation ► Now that the mRNA is created from the DNA during transcription, translation may begin. ► In translation, the appropriate amino acid is matched with the codons (3 bases) in the mRNA sequence to form a protein  Amino acids are the monomers of a protein

Figure 12–17 The Genetic Code Section 12-3 Go to Section:

The players in translation ► mRNA  Holds the genetic code in the sequence of bases ► Codon  3 consecutive bases in the mRNA sequence ► tRNA  Carries the amino acid ► Anticodon  3 consecutive bases on the tRNA sequence ► Ribosome (made of rRNA and proteins)  Has two spaces for mRNA and tRNA to meet and join amino acids

Translation (slide 1 of 2) Messenger RNA Messenger RNA is transcribed in the nucleus. Transfer RNA Translation begins at the start codon AUG. The codons match with the complimentary anticodon on the tRNA. Each tRNA has a specific amino acid attached to it. The ribosome moves over one codon mRNA Start codon Ribosome Methionine PhenylalaninetRNA Lysine Nucleus mRNA

Translation (slide 2 of 2) The Polypeptide “Assembly Line” As the ribosome moves along the mRNA, the amino acid chain is built. tRNAs bring in more amino acids. The ribosome (2 car garage) continues to move and read the codons on the mRNA. mRNA Ribosome Translation direction Lysine tRNA Ribosome Growing polypeptide chain mRNA Completing the Polypeptide The process ends when it reaches a stop codon. The amino acid chain (protein) is released.

mRNA to protein (amino acid)

Determining the Sequence of a Gene ► DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. Such errors are called mutations. Go to Section:

Substitution Insertion Deletion Gene Mutations: Substitution, Insertion, and Deletion Section 12-4 Go to Section:

Overview of translation ► mRNA is created from the DNA during transcription and exits the nucleus ► The AUG codon is the starting point for translation ► Ribosome binds to the mRNA and a tRNA matches its anticodon with the codon ► The tRNA has the amino acid attached to it which becomes part of the protein chain ► Translation will occur until a stop codon is reached

Review 1. DNA to DNA - Purpose of DNA replication  To make copies of the DNA for cell division 2. DNA to RNA – Purpose of transcription  To make a copy of the blueprint that codes for the amino acids (proteins) 3. RNA to protein – Purpose of translation ► Match codons from mRNA to anticodons on tRNA which has the amino acid to form a protein

Homework ► Create an 8 panel cartoon describing the steps of TRANSLATION ► Lab on Monday

Finish 2 day classwork (40 points) ► Create an informational and creative poster showing the process and importance of TRANSLATION ► In color ► 4 or less ► You can use analogies to help illustrate