DNA/RNA/Protein/Trait

WHAT IS DNA? What’s the monomer of DNA (nucleic acid)? What is DNA used for? Where do you find DNA?

D.N.A. On your sheet, draw in the tiger’s face using the half picture first, then draw the picture without the template Try drawing the picture without the template Draw in the tiger’s face. Which one was easier to draw?

DNA Base Pairing and DNA replication

Your Life Story Start with 2 cells, end up with about..? 75 trillion What if something goes wrong?? Every single cell [99.999999%] contains a copy of your DNA, which is like the biggest library ever. The color of your hair, your height, the way your internal organs are structured, how your antibodies work—all of that is written in the language of [what are the monomers of nucleic acids] nucleotides—A, T, G, C. Computers speak binary – your body speaks nucleotide. You would need thousands and thousands and thousands of books just filled with the letters “ATC” to record your genome, which is unique and has never occurred before. Going from 2 copies of your DNA library to trillions is crazy—how can we understand this? Your body has evolved a clever and simple way of ensuring this happens. We’ll also check out if this crazy process goes wrong.

We had one heart; now we made one heart. We’ve done one replication.

We had one heart; now we made one heart. We’ve done one replication.

We had one heart; now we made one heart. We’ve done one replication.

Parent Heart Daughter Hearts Granddaughter Hearts

REPLICATION Parent Heart Daughter Hearts Granddaughter Hearts Repeat – repeat Granddaughter Hearts

Replication Each half of the original DNA molecule is joined with a new complementary DNA strand.

DNA uses the same strategy to copy itself! Parent Heart = Daughter Hearts How is replication similar to drawing using a template, like we did with the tiger? Granddaughter Hearts

What’s DNA? Monomer: Nucleotide

What do you think base pairing means? Discuss: What do you think base pairing means?

Do you see any patterns emerging? C G Base Pairing A T Discuss: Do you see any patterns emerging? G C C G A T A T T A G C

A T G C Base-Pairing Rules All Tigers Can Growl [Based on what you know about semi-conservative replication, why does this have to be true?] Binary, language of nucleotides All Tigers Can Growl

Base-Pairing Rules 1. A-T C-G 2. Adenine-Thymine Guanine-Cytosine 3.

C G A T G C

Applying base-pair rules! Practice Problem: Find the complementary strand to the template strands shown below. 1. CAT 2. GTA CGA GCA 3. GGG ATA CCA TAA GAG AAC AAG TAT TAA

Why does this kind of replication mean where are fewer errors in copying DNA?

Practice question Given What’s missing? A G T ? I think that…I think that…. . I think that…I think that…. . A G T ? Given What’s missing?

Practice question In replication, DNA is copied so that… The replicated strands are made of 1 new strand and 1 original strand The replicated strands are made of 2 new strands The replicated strands are made mostly of new strands with a few pieces of the original strand placed inside

DNA Extraction Lab – with strawberries!! Strawberries are unique –they have 8 copies of each chromosome (lots of DNA!) Materials Purposes:   Dishwasher soap: helps to dissolve the cell membrane, which is made up of a phospholipid bilayer and several proteins. Sodium chloride (salt): helps to remove proteins that are bound to the DNA. It also helps to keep the proteins dissolved in the aqueous layer so they don't precipitate in the alcohol along with the DNA. 91% Isopropyl alcohol: used to precipitate DNA. When DNA comes out of solution, it tends to clump together, or precipitate, which makes it visible. The long strands of DNA will wrap around the stirrer when it is swirled at the interface between the two layers of solution. Make sure the isopropyl alcohol is kept cold until you are about to use it. DNA extraction buffer: The DNA extraction buffer is made up of water, salt, and dishwasher detergent.