To Do

80 copies of nucleotidesIpads out40 copies of organic molecule relooping

worksheet40 copies (on the back?) of DNA replicationm

OCTOBER 15 T H , 2012

DNA Structure!

http://www.msnbc.msn.com/id/49406174/ns/technology_and_science-science/#__utma=14933801.297198480.1342556601.1350238841.1350259800.224&__utmb=14933801.2.10.1350259800&__utmc=14933801&__utmx=-&__utmz=14933801.1342556601.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none)&__utmv=14933801.|8=Earned%20By=msnbc%7Ccover=1^12=Landing%20Content=Mixed=1^13=Landing%20Hostname=www.nbcnews.com=1^30=Visit%20Type%20to%20Content=Earned%20to%20Mixed=1&__utmk=178822436

Do Now

1) List one way that organic molecules are the same and one characteristic that is unique about each.

2) Are organic molecules essential to living things? Explain one way you know.

3) Are nucleic acids essential to living things? Why or why not?

Watson and Crick

What is DNA?

Deoxyribonucleic Acid (DNA) The sugar is DeoxyRibose

DNA is a NUCLEIC ACID

Where is DNA found?

PROKARYOTES: Found in the cytoplasm

 EUKARYOTES: Found in the nucleus

How SIMILAR are you to the person sitting next to you?

You are 99% identical to the person sitting next to you!!

What is DNA made of (the subunits)?

NUCLEOTIDES!!

What are the main parts of a NUCLEOTIDE?

PhosphateSugarNitrogen Base

What are the FOUR NITROGEN BAES?

A = Adenine T = ThymineC = CytosineG = Guanine

What is COMPLIMENTARY BASE PAIRING?

The same bases will ALWAYS pair together!

A pairs with TC pairs with G

ALWAYS!!! (Unless there is a mutation)

Label the parts of a Nucleotide

TRY IT!

ATT ATC GTA TCT CAT ATG TCG

How is a DNA molecule MADE?

Nucleotides come togetherThen, HYDROGEN bonds form between the

nitrogen basesThis makes TWO strands of nucleotides which

twist into a DOUBLE HELIX

What is the SHAPE of DNA?

DOUBLE HELIX It looks like a twisted ladder OR, a spiral staircase

What are HYDROGEN BONDS?

The bonds that form between the nitrogen bases

They are very WEAK and break easily This is how DNA is able to make new copies of itself!

T.B.C.!

How is DNA STORED in eukaryotes?

The DNA is compacted in the CHROMOSOMES and stored in the nucleus

Chromatin is a complex that make up chromosomes (remember from mitosis lecture)

Gene is a portion of DNA that codes for RNA, which codes for trait

A trait is a characteristic of a living thing!

STOP HERE

Day 2: October 16th, 2012

Do Now:What organic molecule is DNA?What is that organic molecule’s monomer?The monomer has 3 parts: What are the 3?Name the 4 nitrogen bases in the nucleotide:

Adenine pairs with _____________Cytosine pairs with _____________

Video on DNA Structure

Replication

The definition of replication: the make an exact copy of an object

DNA replication making 2 new IDENTICLE DNA molecules from 1 DNA molecule

RECAP

Living Organisms have DNA, so what part of STERNGRR does duplicating DNA cover?

DNA must be duplicated in the ‘S’ Synthesis phase of Interphase in order to make 2 IDENTICLE cells!

This must occur because the Nucleus is the “boss” of the cell.

If the nucleus is the boss, who does all the ordering around? The DNA!

DNA must be duplicated so all cells have the right instructions!

So…what’s got to be copied first?! The DNA

Answer these as a summary:

Why might it be important to make exact copies of cells?

Which organelle is the “boss?” of the cell?

Why is it the “boss?”

Who gives all the instructions? How can cells make exact copies?

What must be copied first?

MARSHMALLOW CON’T…

Watch as Ms Kuipers replicates our DNA Molecule

What is DNA REPLICATION?

NEW cells are made by copying OLD cells

Before a cell divides, you have to copy or replicate the DNA

Video of Mitosis Real Time…

Why does DNA REPLICATE?

To get ready for cell division So each new cell has the same exact DNA!

Stations

15 minutes at each stationWorking together to finish the work before

time is calledReasonable noise level!

1. Building DNA 2. DNA Current Event3. Organic Molecules Relooping3. DNA Replication

What are the STEPS for DNA Replication?

1. An Enzyme “UNZIPS” the 2 strands of DNA by breaking the weak Hydrogen bonds

2. New nucleotides are added to the old stand-REVIEW: A = T and C = G

3. Another Enzyme “ZIPS” the strands back up1. What bonds do you think they will re-form?

4. Another enzyme, DNA Polymerase, “proofreads” the strands to make sure there are no MISTAKES!

What is the ROLE of ENZYMES?

Enzymes help to:1. Split the DNA in half2. Put DNA back together3. Proofread for any mistakes in

the base pairs

How is DNA Replication SEMI-CONSERVATIVE?

When the DNA copies itself, it always has HALF of the parental (OLD) strand and HALD of the daughter (NEW) strand

In other words: the DNA is HALF OLD and HALF NEW

DNA Video Clip

http://www.youtube.com/watch?v=zdDkiRw1PdU&feature=related

DNA Replication Practice

DNA strand: ATGGCComplementary DNA strand: _________

Write your own DNA strand

Then, pass to a partner and have them decode it!

Challenge Question

If 15% of bases are Cs, how many must be Ts? We will answer as a class.