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Happy Tuesday!! You need one of each of the papers from the welcome table. Clear your desks and prepare for the quiz.
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Supply managers, please get the supply bins for your group
Happy Tuesday!! Supply managers, please get the supply bins for your group Quickly Color Circles gray Adenines green Thymines orange Guanines red Cytosines blue
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(Deoxyribonucleic Acid)
DNA (Deoxyribonucleic Acid) History and Structure C10L28C12
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Chromosomes are made of DNA
Chromosomes and DNA During Mitosis we can see Chromosomes Chromosomes are made of DNA
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Chromosomes and DNA
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Today’s Goals Item 1 What is DNA? Item 2 DNA History Item 3
DNA Structure Item 4 DNA Nitrogen Bases Item 5 Chargaff's Rule
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What is DNA? DNA holds all the genetic information that determines an organism’s traits. Hair Color Height Skin Tone Eye Color
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What is DNA? Within the structure of DNA is the information for life—the complete instructions for manufacturing all the proteins for an organism. DNA achieves its control by determining the structure of proteins. Enzymes (a type of protein) control the chemical reactions needed for life. Eating, running, even thinking
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Today’s Goals Item 1 What is DNA? Item 2 DNA History
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Johann Friedrich Meischer
1869 The first scientist to identify and isolate DNA He called it nuclein
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Important clues to the structure of DNA
Rosalind Franklin 1952 Studied DNA structure with X-ray diffraction Important clues to the structure of DNA Twisted strands (helix) Angle suggested 2 strands ( double-helix) Nitrogen bases near the center of the molecule
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James Watson and Francis Crick
1953 Built a DNA model based on the clues from Franklins X-ray diffraction
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Today’s Goals Item 1 What is DNA? Item 2 DNA History Item 3
DNA Structure
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DNA is a Double Helix A double helix looks like a twisted ladder.
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The Double Helix Building Blocks
A DNA strand is a polymer. They are very long! It’s length is what allows DNA to hold so much information The repeating subunits of DNA are called nucleotides
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Nucleotide Structure Composed of 3 parts Phosphate Nitrogen Base
There are 4 possible bases. Broken down into 2 categories Phosphate Nitrogen Base Deoxyribose Sugar
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Nucleotide Structure The phosphate groups and deoxyribose (sugar) molecules bond to form the backbone of the chain The nitrogenous bases stick out like the teeth of a zipper.
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Today’s Goals Item 1 What is DNA? Item 2 DNA History Item 3
DNA Structure Item 4 DNA Nitrogen Bases
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Types of Nitrogen bases
There are two types of nitrogen bases Purines Pyrimidines Pyrimadines have one ring Purines have two rings
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Types of Nitrogen bases
There are two types of nitrogen bases Purines Pyrimidines
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Today’s Goals Item 1 What is DNA? Item 2 DNA History Item 3
DNA Structure Item 4 DNA Nitrogen Bases Item 5 Chargaff's Rule
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How the double helix is formed
Nitrogen bases bond to one another to connect the two strands But only certain bases can bond to one another
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Chargaff’s Rule – Base Pairing
1 Purine must bond to 1 pyrimadine Adenine only bonds to Thymine Guanine only bonds to Cytosine At The Grand Canyon
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OVERVIEW
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(B.5C) Unspecialized cells that can become more than one type of cell are called…
Stem cells
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