DNA Transcription and Translation HS-LS3-1. Ask questions to clarify relationships about the role of DNA and chromosomes in coding the instructions for characteristic traits passed from parents to offspring. The students will be able identify and describe the processes of translation and transcription Warm up Check Watch the video and answer the following questions https://www.youtube.com/watch?v=2zAGAmTkZNY&t=198s https://www.youtube.com/watch?v=2zAGAmTkZNY&t=198s 1- What are the two processes that are involved in the formation of Protein? 2- Where in the cell does each process happen ? Task1 Read the given passage and answer the following questions 1-Define transcription 2-What is stated in the central dogma? 3-What are the three main types of RNA? Which is translated into a protein? Task2 Read the given passage and answer the following questions Define translation What is a codon? What role does tRNA play in translation? What forms the bond between neighboring amino acids? Task3 https://www.youtube.com/watch?v=2zAGAmTkZNY&t=198s https://www.youtube.com/watch?v=WvZ1PK8Uxao Refer to the link and answer the following questions List the types and function of the three types of RNA Summarize the process of translation and transcription Soon after his discovery of DNA structure, Francis Crick defined the central dogma of molecular biology, which states that information flows in one direction, from DNA to RNA to proteins. The central dogma involves three processes . • Replication, as you just learned, copies DNA • Transcription converts a DNA message into an intermediate molecule, called RNA Translation interprets an RNA message into a string of amino acids, called a polypeptide. - In prokaryotic cells, replication, transcription, and translation all occur in the cytoplasm at approximately the same time. In eukaryotic cells, these processes are separated both in location and time. Replication and transcription occur in the nucleus, whereas translation occurs in the cytoplasm Types of RNA Definition: Transcription Transcription Nucleus Location DNA Template (What is read) To change DNA into a form that can make a protein Purpose Messenger RNA (mRNA) Outcome (End result) Definition: Translation Translation Location Cytoplasm (by ribosome) Template (What is read) mRNA Purpose Amino acids assembled in particular order to make a protein Outcome (End result) Protein (polypeptide) (Amino acid) Start and Stop Codons Start Codon: Begins translation AUG (universal start codon) ALSO Codes for methionine(amino acid) (Met) Sometimes GUG or UUG Stop Codon: Ends translation UGA, UAA, UAG Transcription(To copy) occurs in 3 steps Initiation: RNA polymerase binds to DNA at ‘promoter’ untwists the double helix 10 to 20 bases at a time Elongation: RNA polymerase builds mRNA DNA: A Uses complimentary base pairing RNA: Remember: thymine (T) is replaced by uracil (U) Termination: RNA polymerase reaches end of gene. Stops transcribing Double helix reforms as mRNA molecule peels away. End Result: mRNA breaks away from DNA mRNA exits nucleus T G C A A U A C G U U Translation: ‘new language’ Initiation: Ribosome binds at a specific sequence on the mRNA. The ribosome moves along the mRNA three nucleotides at a time. This is called a codon. Each set of three codon) codes for an amino acid. Elongation: Ribosome moves along mRNA From mRNA 5’ end 3 nucleotides of mRNA = codon = amino acid The “interpreter” tRNA delivers the proper complimentary base to the ribosome. The anticodon( tRNA) binds by complimentary base pairing to the nucleotides of the codon. Example: if the codon on a mRNA is UUU, a tRNA with an AAA anticodon will bind to it. The ribosome links adjacent amino acids with a peptide bond, causing the amino acid to let go of it tRNA. The finished protein has a sequence of amino acids that have been determined by the mRNA base sequence which has been translated by the tRNA. The ribosome then adds each amino acid and the polypeptide chain is elongated. Elongation occurs until a stop signal occurs. Termination: Ribosome reaches stop codon and stops translating End Result: Ribosome falls off mRNA and Protein (polypeptide chain) is released The Whole Picture Next amino acid to be added to polypeptide Growing polypeptide tRNA mRNA B. Copying down information in DNA into an mRNA molecule C. tRNA forming a sequence of amino acids in a protein d. Anticodons being linked from tRNA in a specific sequence exit ticket 2. Translation is the process where A. the code information in mRNA is translated into a sequence of amino acids in a protein B. DNA is making a copy of itself C. Changes are being made to DNA D. DNA is making RNA 3. What type of molecule being produced is shown below? A. New DNA B. mRNA C. Protein D. Lipid 4. For the diagram shown on the left, describe what process is taking place and where this process takes place inside of the cell.