2.How are proteins made in a cell? DO NOW 1.What controls cell activity? 3. What is the 4 th major biochemical molecule in the body? 4. What controls all life functions?

What is DNA? It is the genetic information that is passed from generation to generation. Where is it found? It is found in the nucleus of every living cell. No DNA = Death! Does every single cell in our body have the same DNA? Yes!!! But WHY????

THE BUILDING BLOCKS OF DNA: Nucleotides Nitrogenous Bases (A T G C) Sugar: Deoxyribose Phosphate Group PHOSPHATE GROUPS SUGARS NITROGEN BASES

Nitrogenous Bases 1.Adenine 2.Thymine These pairs 3.Guanine 4.Cytosine Represented as interlocking shapes and are joined to the sugar of the nucleic acid A T

ATCGATCG A Adenine T Thymine C Cytosine G Guanine SUGAR- PHOSPHATE BACKBONE NUCLEOTIDE HYDROGEN BONDS A T C G

Who discovered the shape of DNA? Watson and Crick -- Won The Nobel Prize What do they call this model? A Double Helix Made of: 2 Strands of alternating Sugar & Phosphate molecules ( sides of ladder ) Held together by 4 nitrogen bases. (A-T G-C) ( rungs of ladder ) SUGAR- PHOSPHATE BACKBONE NUCLEOTIDE HYDROGEN BONDS

A always pairs with T G always pairs with C on your paper, try to figure out the 2 nd, complimentary DNA strand for this: AGGGCTTACACATTT TCCCGAATGTGTAAA

THE FUNCTION OF DNA What is replication: Making an exact copy. When would DNA need to do this? How does it happen?

Functions of Nucleic Acids 1.DNA- Contains the hereditary material inside nucleus 2.RNA- ________________________________ made of Nucleic Nucleotides Nitrogenous AcidsBases (A,T,C,G)

The replication of DNA The process of DNA replication occurs: -Origins of replication with DNA polymerase ** this enzyme makes the covalent bonds between the nucleotides of the new DNA strand Replication Replication Clip 1 ClipClip 2

A G A T G C T C T A C G T T A A C C A A T T G G 5’ 3’ Parent DNA Molecule DNA Helicase Enzyme 3’ 5’

A G A T G C T C T A C G T T A A C C A A T T G G 3’5’ 3’ DNA Helicase Enzyme

A C G T T DNA Polymerase Enzymes A G A T G C T C T A A C C A A T T G 3’ 5’ 3’ 5’ G

T T New Strands of DNA A G A T G C T C T A C G A A C C A T A T G 3’ 5’ 3’ 5’ G C C A A Free Nucleotides C A A C G T

T T New Strands of DNA A G A T G C T C T A C G A A C C A T A T G 3’ 5’ 3’ 5’ G C C A A C A A C G T A A T T T

On the “Leading Strand” DNA Polymerase continuously adds new nucleotides, as it follows DNA Helicase On the “Lagging Strand” DNA Polymerase runs in the opposite direction of the Helicase, and therefore must make a series of discontinuous pieces (or fragments). 3’ 5’ A G A T G C T A C G T T A A C C A T T A G G 3’ 5’ T C T A C G T T A A C C A T T 3’ 5’ A G G

3’ 5’ A G A T G C T A C G T T A A C C A T T A G G 3’ 5’ T C T A C G T T A A C C A T T 3’ 5’ A G G

3’ 5’ A G A T G C T A C G T T A A C C A T T A G G 3’ 5’ T C T A C G T T A A C C A T T 3’ 5’ A G G

3’ 5’ A G A T G C T A C G T T A A C C A T T A G G 3’ 5’ T C T A C G T T A A C C A T T 3’ 5’ A G G

3’ 5’ A G A T G C T A C G T T A A C C A T T A G G 3’ 5’ T C T A C G T T A A C C A T T 3’ 5’ A G G

3’ 5’ A G A T G C T A C G T T A A C C A T T A G G 3’ 5’ T C T A C G T T A A C C A T T 3’ 5’ A G G

T 3’ 5’ A G A T G C T A C G T T A A C C A T T A G G 3’ 5’ T C T A C G T T A A C C A T T 3’ 5’ A G G C T A G A

T 3’ 5’ A G A T G C T A C G T T A A C C A T T A G G 3’ 5’ T C T A C G T T A A C C A T T 3’ 5’ A G G C T A G A 3’ G C

T 5’ A G A T G C T A C G T T A A C C A T T A G G 3’ 5’ T C T A C G T T A A C C A T T 3’ 5’ A G G C T A G A 3’ G C

T 5’ A G A T G C T A C G T T A A C C A T T A G G 3’ 5’ T C T A C G T T A A C C A T T 3’ 5’ A G G C T A G A 3’ G C On the “Lagging Strand” DNA Polymerase Leaves a gap in the backbone of the newly Forming strand because It is unable to form the Last covalent bond In the backbone. 3’

DNA Ligase enzyme can connect the two fragments by forming a covalent bond between them. T 3’ 5’ A G A T G C T A C G T T A A C C A T T A G G 3’ 5’ T C T A C G T T A A C C A T T 3’ 5’ A G G C T A G A 3’ G C

T 5’ A G A T G C T A C G T T A A C C A T T A G G 3’ T C T A C G T T A A C C A T T 5’ A G G C T A G A 3’ G C We now have two identical daughter molecules of DNA, and the cell is ready for a Mitosis or a Meiosis division.

DNA Replication ___________________ itself to allow mitosis and meiosis to occur; it passes genetic info on to the new cells Steps in replication: DNA Molecule DNA “Unzips” Free nucleotides join the unzipped strands A TATATAT T ATATATA C GCGCGCG

DNA Replication clip part 1 DNA Replication clip part 2

So how is RNA different from DNA? They are both organic molecules called Nucleic Acids. What are the subunits of RNA? Nucleotides – similar to DNA Sugar -- Ribose Nitrogenous Base Phosphate

RNA – RiboNucleic Acid Made of nucleotides too, but some differences: A = Adenine C= Cytosine U = Uracil G = Guanine Sugar = Ribose Phosphate Group

Transcription: The making of mRNA from DNA biomovies\DNAtran scription.mov Transcription Clip

Steps in Transcription DNA DNA Codon mRNA Template A TAU GC every 3 nit base is a GC Codon CG template for Codon CG CGCG TA Unzips TA Codon AT (Template used to make mRNA) AU Codons will go to the ribosome to be “read” It is the nitrogenous bases that determine the codon! Template strand “Transcription” Unzips at weak H bond

Transcription Animation Shared Server

The 3 Types of RNA: TypesNameFunctionFound? mRNAMessenger RNATranscribed from the DNA template, and replicates the DNA All over the cell tRNATransfer RNATranslates the 3 letter codon of the mRNA to the amino acids Anticodon- Codon Cytoplasm rRNARibsomal RNAHold the “m” and “t” together

Protein Synthesis/ Transcription

biomovies\DNAtra nslation.mov Translation Clip TRANSLATION

Protein Synthesis- What we already know 1. DNA is a code. The code is found in as a sequence of __________________ 2. Instructions for making __________________ 3. Polypeptide is another name for _____________ 4. Proteins are long chains of _________________ 5. Proteins make up _________________________ 6. Proteins are made in the ___________________ ribosome Muscles, hair/ fur, nutrient storage Amino acids proteins nucleotides biomovies\protein synthesis.mov

Translation = Protein Synthesis STEPS TO MAKING A PROTEIN 1.DNA lives in the _______________________ 2.A short section of the double helix ____________ and the 2 sides of the DNA “ladder” ____________ from each other 3. A copy of the short section of DNA is made- just 1 side-so it is ____________ stranded. This copy is called ________________ RNA (mRNA) ** copy not like DNA- RNA has ________________ Nucleus singl e messeng er uracil Move away split

4. How is mRNA different? -_____________ stranded -Allowed to leave the _____________ -Does not have the ______ nucleotide. It uses ________ 5. The mRNA takes the code to a __________ in the cell 6. Ribosomes can only read _____ letters of a code at a time. They start reading the code in groups of 3 called __________________ singl e nucle us T U 3 codo n riboso me

7. Each time the ribosome reads 3 letters on the mRNA, it calls for another molecule ________ which carries an amino acid. tRNA picks up the amino acid that is needed and drops it off There are hundreds of tRNAs. So if the codon for the mRNA is GGG- ribosome tells tRNA to bring the opposite code of ________. This is the exact opposite so its called _____________. 8. We’re trying to make a protein so each time a tRNA brings an ___________________ to the ribosome, they link together. And now we have a PROTEIN. tRN A CCC Anti codon Amino acid

DNA mRN A prote in Transcripti on Translat ion

Amino Acids t-RNA’s m-RNA 3’ 5’ Ribosome START CODON

Amino Acids t-RNA’s m-RNA 3’ 5’ START CODON Peptide bond forms Ribosome

Amino Acids t-RNA’s m-RNA 3’ 5’ Ribosome

Amino Acids t-RNA’s m-RNA 3’ 5’ Ribosome

Amino Acids t-RNA’s m-RNA New Protein 3’ 5’ Ribosome

Amino Acids t-RNA’s m-RNA New Protein 3’ 5’ Ribosome

Amino Acids t-RNA’s m-RNA New Protein 3’ 5’ Ribosome

Amino Acids t-RNA’s m-RNA New Protein 3’ 5’ Ribosome

Amino Acids t-RNA’s New Protein 3’ 5’ Ribosome

Amino Acids t-RNA’s 3’ 5’ New Protein STOP CODON Ribosome

Amino Acids t-RNA’s m-RNA New Protein 3’ 5’

Amino Acids t-RNA’s m-RNA New Protein 3’ 5’ NH 2 COOH

3’ 5’ GAC CUG GAC AMINO ACID = ASPARTATE AMINO ACID = LEUCINE

Ok, so what kinds of things can go wrong????

Gene Mutations! Any change in the order of bases on the DNA is a gene mutation. What are some kinds of mutations? Substitution- 1 letter or gene changed Deletion- 1 or more letters deleted Addition- 1 or more letters added Inversion- wrong order