DNA to RNA
The first step in - How DNA makes you
How to Bake Grandma’s Cookies(Another Food Analogy to Help You Learn Biology)
1. Copy the recipe from Grandma’s family secret recipe file.
• Location of recipe - Grandma’s house
• Product - Written instructions to make the best cookies in Quakertown, PA
Grandma lives in a retirement home, so she doesn’t cook.
You will have to copy Grandma’s recipe in order to leave Grandma’s & go to your kitchen where you will find the ingredients and utensils to make the cookies.
2. Read and follow instructions
• Add: correct ingredientscorrect amountscorrect order
• bake for required time• Product:
Best cookies in town!
How is this analogous to biology?
• How does the information (recipe) produce the cookies (product)?
• How does the information in genes (sections of DNA) produce the proteins (products) that make our traits?
• What are the “products” that cause you to look and function as you?
Review: Proteins• Polymers of amino acids (monomers) • The Order of Amino Acids determines the 3D shape
of a protein• Structure (3-D) determines function• 7 categories:
1. Structure2. Movement 3. Storage 4. Defense 5. Transport 6. Signaling 7. Enzymes
DNA contains the “recipe” for every protein in your body
Information is copied in the nucleus
Copy leaves nucleus cytoplasm
Information used to assemble proteins
• Trait: freckles, bent pinky, floppy earlobes, curly hair
The Big Picture: 2 steps in protein synthesis
1. Transcription information from gene is copied
2. Translation Information is used to assemble amino acids into proteins
Physical Traits are determined by those proteins
DNA – Original Text of Information
mRNA - Working copy of instructions
Three types of RNA:
Messenger RNA (mRNA) Copies information from DNA
Transfer RNA (tRNA) Transports correct amino acids to build protein
Ribosomal RNA (rRNA) Helps form ribosomes: the workbench where proteins are assembled
Transcription: Why
• Information from a single gene is copied to make protein
• Need to protect DNA in nucleus
Transcription: WhatInformation from a gene is copied to produce each protein.
DNA mRNA Protein
Transcription: Where
• Nucleus of cell
Transcription: How
Stop! Check Your Understanding
Complete the DNA RNA chart
Initiation - Begin at Promoter region
Elongation – RNA polymerase adds nucleotides through the coding region
Termination – Ends at the termination sequence. mRNA is now complete
Transcription details
• Initiation: Promoter identifies region to be transcribed• Elongation - Coding region has information for mRNA• RNA polymerase adds nucleotides to mRNA• Termination - ends transcript• mRNA is “edited” before leaving nucleus
Transcription: How
• Transcription Complete
Transcription: What’s Next?• The product is an mRNA copy of DNA information
to make protein
• After transcription is complete: DNA – forms Hydrogen bonds and reforms double helix mRNA is edited (remove introns, exons are to be expressed)mRNA leaves the nucleus and enters cytoplasm for translation
Watch transcription in action (DNAi)
• click “copying the code”• click putting it together• click Transcription• After viewing this WAY COOL
movie, click interactive and make your own RNA.
• Transcribe a gene (DNAi)
Please summarize the process of transcription in your own words
• RNA polymerase transcribes a gene from DNA by adding RNA nucleotides until it reaches a termination sequence. The mRNA is edited to remove introns before leaving through a nuclear pore so that translation can happen in the cytoplasm.