dna to rna the first step in - how dna makes you

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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: 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

DNA

mRNA

RNA polymerase

DNA

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: 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.

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