understanding dna deoxyribonucleic acid double helix: two strands twisted around each other like a...

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Understanding DNA D eoxyribon uc leic A cid Double Helix: Two strands twisted around each other like a winding staircase

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Page 1: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

Understanding DNA

Deoxyribonucleic Acid

Double Helix: Two strands twisted around each other like a winding staircase

Page 2: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

Rosalind Franklin & Maurice Wilkins

Page 3: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

James Watson & Francis Crick

Page 4: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

very large linear molecules

very large linear molecules

examples: DNA and examples: DNA and RNARNA

examples: DNA and examples: DNA and RNARNA

sugar

phosphate

nitrogen

base

nucleotide

store genetic store genetic information, help to information, help to

make proteinsmake proteins

store genetic store genetic information, help to information, help to

make proteinsmake proteins

Page 5: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

Nucleotides A. Sugar (deoxyribose) B. Phosphate Group C. Nitrogen Bases

A

B

C

Page 6: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

Erwin Chargaff

A T

C G

Page 7: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

Rules for Base Pairing:

B.     Adenine = Thymine (A = T)

A.     Cytosine Guanine (C G)

the lines between the letters are hydrogen bonds

Page 8: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase
Page 9: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

* stores genetic information

What is the function of DNA?

Page 10: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

C

G

A

A

T

G

Sugar

Phosphate Nitrogen

Bases

Page 11: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase
Page 12: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

Fun Facts

If you wrote down all of the bases in one cell, you would fill a stack of 1,000 phone books with A's, T's, G's and C's

Page 13: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

Fun Facts

If you unraveled all your chromosomes from all of your cells and laid out the DNA end to end, the strands would stretch from the Earth to the Moon about 6,000 times.

Page 14: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

DNA Replication

Page 15: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

DNA ReplicationResults in two identical DNA

strands 1. DNA helicase separates

or“unwinds” complementary nucleotide strands.

2. DNA polymerases move along each DNA strand adding nucleotides at the replication fork.

3. Each DNA molecule is composed of one old and one new strand.

Page 16: Understanding DNA Deoxyribonucleic Acid Double Helix: Two strands twisted around each other like a winding staircase

Errors

DNA polymerases act as proofreaders and make corrections if the wrong nucleotide is added.