DNA to PROTEIN CHAPTER 12 DEOXYRIBONUCLEIC ACID

DNA: replication and protein synthesis

Where have we seen DNA being replicated? MITOSIS AND MEIOSIS

Building blocks of DNA: Nucleotides

The sugar The phosphate Deoxyribose

The nitrogenous bases The Purines Why are these called nitrogenous bases?

The nitrogenous bases The Pyrimidines How are the pyrimidines different from the purines?

Four different Nucleotides BASIC STRUCTURE

DNA is a polymer formed by base pairing : Base pairing rule

The Double Helix A. The overall shape of DNA is described as a double helix (a twisted ladder). B. What force holds the two strands together?

How are DNA and RNA similar? DNA is composed of nucleotides and RNA is composed of nucleotides

How are DNA and RNA different?

DNA… Nucleotides = deoxyribose sugar Double helix structure Stays inside nucleus RNA… Nuleotides = ribose sugar Single-strand structure Located both inside and outside of nucleus Uracil instead of thymine

DNA Replication Set up your DNA by applying the base pair rules Strand 1 Complementary Strand 2 A T C G

Enzymes involved in DNA replication Helicase – opens the double helix to allow for replication DNA polymerase – reads the original DNA strand and lays down complementary bases Ligase – glues the newly formed DNA together

DNA replication practice You are DNA polymerase. Helicase has opened the DNA strand – read each side and produce the complementary copies. __________________________________ A G G T A A C C G G T T A C G A T T A T T C C A T T G G C C A A T G C T A A T A A G G T A A C C G G T T A C G A T T A T T C C A T T G G C C A A T G C T A A T A

PARTNER PRACTICE Person one uses their nucleotides as free nucleotides Person two works with partner to replicate their original strand Discuss the enzymes as you model the process

Do # 9 IN YOUR NOTES TO PRACTICE BASE PAIRING RULES AGAIN __________________________________ A G T C C G T T A G T T C A G G C A A T C A

Hydrogen bonds Nucleotide Sugar-phosphate backbone Key Adenine (A) Thymine (T) Cytosine (C) Guanine (G) Figure 12–7 Structure of DNA Section 12-1

Use your text to complete the diagram and provide written details for the process shown

Homework Complete labeling of notes cover Complete DNA replication labeling and details Complete Section 10-1 Review – accuracy!

Protein Synthesis= transcription and translation DNA contains all the information for your traits – the genes These genes are blueprints and need to remain safe – kept inside the nucleus Copies can be made though – a messenger

Genotype  Phenotype DNA  mRNA  tRNA  PROTEIN Transcription Translation (DNA to mRNA) (mRNA – tRNA to protein)

fromtoto make up Concept Map Section 12-3 also calledwhich functions toalso called which functions to can be RNA Messenger RNA Ribosomal RNA Transfer RNA mRNACarry instructions rRNA Combine with proteins tRNA Bring amino acids to ribosome DNARibosomeRibosomes

Transcription #8 RNA polymerase reads one of the DNA strands and makes a complementary mRNA #10 transcription details Occurs in the nucleus The gene sequence on DNA gets transcribed Promoter region on DNA marks where transcription should start and terminator region marks where it should stop

mRNA RNA polymerase – key enzyme mRNA is a “copy” of the gene sequence and can leave the nucleus mRNA finds its way to a ribosme and the next step in making a protein can occur - TRANSLATION CLICK ON PICTURE FOR ANIMATION ON TRANSCRIPTION

mRNA No T (thymine) so when it reads the nucleotide A on DNA it matches it with ____? Do #11 in notes

#12 – TRANSLATION and tRNA Once mRNA is made it attaches to a ribosome tRNA = transfer RNA and they carry amino acids Amino acids are the building blocks of proteins (remember?)

Translation Ribosomes are the site of protein synthesis Click here to see mRNA and tRNA work together at that ribosome to build a protein Click here to see mRNA and tRNA work together at that ribosome to build a protein

Codon = mRNA Anti-codon = tRNA

Copy down this DNA sequence This is the template strand of DNA, complete the complementary strand sequence below the template. TRANSCRIPTION: read the template DNA strand and write the complementary mRNA TRANSLATION: based on your mRNA, determine the proper amino acid sequence CAG GTG AAT TGG GGC CTC CAC TTT

Copy this DNA sequence down CAG GTG AAT TGG GGC CAC CAC TTT REPEAT ALL THE STEPS AND DETERMINE THE AMINO ACID SEQUENCE FOR THIS GENE!

COMPARE: what is the mistake? CAG GTG AAT TGG GGC CTC CAC TTT CAG GTG AAT TGG GGC CAC CAC TTT

One incorrect amino acid

GENOTYPE to PHENOTYPE

Deletion Duplication Inversion Translocation Figure 12–20 Chromosomal Mutations Section 12-4

Let’s Review DNA Structure is a _____ ______ DNA is composed of __________ What are four that make up DNA? A T C G

PurinesPyrimidines AdenineGuanine CytosineThymine Phosphate group Deoxyribose Figure 12–5 DNA Nucleotides Section 12-1

Hydrogen bonds Nucleotide Sugar-phosphate backbone Key Adenine (A) Thymine (T) Cytosine (C) Guanine (G) Figure 12–7 Structure of DNA Section 12-1

Use your text to complete the diagram and provide written details for the process shown

fromtoto make up Concept Map Section 12-3 also calledwhich functions toalso called which functions to can be RNA Messenger RNA Ribosomal RNA Transfer RNA mRNACarry instructions rRNA Combine with proteins tRNA Bring amino acids to ribosome DNARibosomeRibosomes

RNA DNA RNA polymerase Figure 12–14 Transcription Section 12-3 Adenine (DNA and RNA) Cystosine (DNA and RNA) Guanine(DNA and RNA) Thymine (DNA only) Uracil (RNA only)