DNA Deoxyribonucleic Acid

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DNA Deoxyribonucleic AcidThe Blueprint of Life

• I. DNA Structure Function

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A. What is DNA?

• 1. Organic molecule
• 2. Nucleic acid

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B.Where is it located?

• 1. Nucleus
• 2. Chromosomes

X
DNA
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Chromosomes in Nucleus
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C. Structure of DNA

• Nucleotides
• a. Phosphoric Acid
• b. Deoxyribose sugar
• c. Nitrogenous bases
• Adenine-Thymine
• Guanine-Cytosine
• 2. Ladder Shape
• 3. Double strand, helix twist

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Ladder Shape (Sides Rungs)
Sugar Acid Sugar Acid Sugar

• Sides
• Phosphoric Acid
• Sugar
• Phosphoric Acid
• Rungs
• A-T
• T-A
• G-C
• C-G

• T-A
• G-C
• C-G
• A-T

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Watson Cricks Double helix
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D. What is DNAs Function?

• Hereditary Instructions
• Chemical code for every trait
• Blueprint for making Proteins

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Chromosome DNA Code
Hair Color

• Genes
• Segments of DNA
• Code for a trait

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Eye Color
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DNA Chromosome Code

• Triplets
• Sets of 3 Nucleotides
• Code for
• Trait

Acid Acid Sugar-T-A-Sugar Acid
Acid Sugar-G-C-Sugar Acid
Acid Sugar-C-G-Sugar
X
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DNA Chromosome Code
- -
Like Morse Code Hair
Or DNA A-T A-T G-C C-G T-A C-G
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DNA Replication

• Chromosomes double
• Mitosis
• Late Interphase
• 2n to 4n

2N
2N
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E. Steps for DNA Replication

• DNA untwists
• DNA unzips
• Enzyme Helicase
• Replication Fork
• RNA Primer
• Enzyme Primase
• Corresponding base pairs
• Line up
• In sets of 3 nucleotides
• Triplets or codons
• DNA reforms
• 2 strands twist into helix

Identical Strand
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DNA Replication Cont

• 4. base pairs / Complementary Strand
• Line up
• In sets of 3 nucleotides Triplets
• Or codons
• Enzyme DNA Polymerase III
• Fragments Connect
• Enzyme Ligase

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DNA Replication Cont

• RNA is replaces and proofread
• Enzyme Polymerase I
• 7. DNA reforms and twists to form double helix

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RNA Ribonucleic AcidDNA messenger taxi

• II. RNA Structure Function

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A. What is RNA?

• Organic Molecule
• Nucleic Acid
• mRNA
• messenger
• tRNA
• transfer

Ribonucleic Acid
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B. Where is RNA located?

1. mRNA in nucleus cytoplasm
2. tRNA only in cytoplasm

mRNA
mRNA
tRNA
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B. What is RNAs structure?

• Nucleotides
• a. Phosphoric Acid
• b. Ribose sugar
• c. Nitrogenous
• Bases
• Adenine-Uracil
• Guanine-Cytocine
• 2. Single Strand
• 3. No Twisted helix

• Acid
• Sugar-Base
• Acid
• Sugar-Base
• Acid
• Sugar-Base
• Acid
• Sugar-Base

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Comparison of RNA DNA

• Acid
• Sugar-Base
• Acid
• Sugar-Base
• Acid
• Sugar-Base
• Acid
• Sugar-Base

• Acid Acid
• Sugar-Base-Sugar
• Acid Acid
• Sugar-Base-Sugar
• Acid Acid
• Sugar-Base-Sugar
• Acid Acid

Uracil
Thymine
Deoxy-ribose
Ribose
RNA
DNA Ladder
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D. What are RNAs functions

• mRNA
• Copies the DNA code
• Deliveries message to Ribosome
• Protein Factories

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Why not send the original DNA code out?
Original DNA

• DNA might be damaged!
• mRNA components are reused
• To copy more messages

mRNA copy
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RNA function cont.

• tRNA
• in cytoplasm
• Picks up an amino acid
• Taxis the aa to the Ribosome protein factories

Amino acid
tRNA
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III. Protein Synthesis

• Assembling Proteins from the DNA Instructions

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A. Transcription

• mRNA is copied off of DNA
• In nucleus
• Steps
• DNA untwists
• DNA unzips
• RNA codons line up

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Transcription

• mRNA has
• Ribose sugar
• Uracil instead of thymine bases
• Nuclear membrane allows it to leave!

mRNA
A T C G
U A G C
I
I
I
DNA Code
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Transcription in The nucleus
DNA
mRNA copy
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B. Translation

• Conversion of the message (mRNA Code)
• Into a protein
• By the ribosome factories

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B.Translation
tRNA taxi
A

1. mRNA arrives at the Ribosome
2. tRNA picks up an amino acid
3. tRNA delivers the aa to the ribosome
4. aa are assembled into polypeptide proteins

U
C
G
U A G C
mRNA code
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4. Polypeptide Chain of amino acids grows
2. Peptide bond forms 3. tRNA leaves ribosome

• tRNA delivers
• amino acid

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Summary

• Protein Synthesis
• Transcrition
• Make mRNA
• From DNA
• Translation
• Make protein
• Off mRNA code
• Using amino acids

• DNA Replication
• Make duplicate DNA
• In nucleus
• Copy the chromosomes
• For Mitosis