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DNA. By: Mr. Kauffman. Outline. DNA background information Discovering DNA DNA structure How DNA works Storing DNA. DNA Background Information. DNA : Deoxyribonucleic Acid It is the genetic/hereditary material found in all cells Stored in the nucleus
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DNA By: Mr. Kauffman
Outline • DNA background information • Discovering DNA • DNA structure • How DNA works • Storing DNA
DNA Background Information • DNA: Deoxyribonucleic Acid • It is the genetic/hereditary material found in all cells • Stored in the nucleus • Contains the information that determines what we look like
DNA Background Information Contains the information to control a cell’s growth and function, but… Only tells how to make things Other parts (proteins) of the cells actually do the work
DNA Background Information • DNA Analogy • DNA is like a cookbook • It tells how to make something, but it doesn’t actually make it • Your DNA contains the instructions for how to make you
DNA Background Information • Every “normal” cell in your body has the same DNA in it • Skin and muscle cells are normal cells • When a cell divides, the DNA inside the cell is copied and each new cell gets 1 copy of it
Discovering DNA • Scientists have known about DNA since the 1800’s • 1952 • Rosalind Franklin discovered that DNA was made up of 2 chains in a spiral shape • 1953 • James Watson and Francis Crick made a model of DNA
DNA Structure • Known as a Double Helix • Meaning there are 2 sides in a spiral shape • More commonly called a twisted ladder
DNA Structure Outer parts of the DNA ladder are called the sugar-phosphate backbone Alternating sections of sugar and phosphate
DNA Structure • The rungs of the DNA ladder are made up of nitrogen bases • There are 4 types of nitrogen bases 1. Adenine (A) 2. Cytosine (C) 3. Guanine (G) 4. Thymine (T) • The bases are always found in pairs • Adenine (A) always pairs with Thymine (T) • Cytosine (C) always pairs with Guanine (G) • They fit together like puzzle pieces
DNA structure • Draw the picture on the left in your notes • Provide the base that each base you have been given would pair with
How DNA works • The sequence of the DNA bases determines the information contained in the DNA • A sequence of 3 bases is called a codon • A codon = an amino acid • There are 20 different amino acids • Each one is controlled by a specific set of 3 bases • ACGGCAATTGCTTTTAAGCCA • ACG , GCA , ATT , GCT , TTT, AAG , CCA
Storing DNA • DNA is stored in the nucleus of the cell • Stored as chromosomes • How many chromosomes do humans have? • Every “normal” human cell has 46 single chromosomes, or 23 pairs of chromosomes • Each chromosome contains DNA with different information in it
Storing DNA Human Chromosome Chart
Storing DNA Actual Human Chromosomes