1. DNA
Structure

2. DNA Structure
DNA consists of two molecules that are arranged into a ladder-like structure called a Double Helix.
A molecule of DNA is made up of millions of tiny subunits called Nucleotides.
Each nucleotide consists of:
Phosphate group
Pentose sugar
Nitrogenous base

3. Nucleotides
Phosphate
Nitrogenous
Base
Pentose
Sugar

4. Nucleotides
The phosphate and sugar form the backbone of the DNA molecule, whereas the bases form the “rungs”.
There are four types of nitrogenous bases.

5. Nucleotides A
Adenine T
Thymine C
Cytosine G
Guanine

6. Nucleotides Each base will only bond with one other specific base.
Adenine (A)
Thymine (T)
Cytosine (C)
Guanine (G)
Form a base pair.
Form a base pair.

7. DNA Structure
Because of this complementary base pairing, the order of the bases in one strand determines the order of the bases in the other strand.

8. A C T G G A T C

9. Chargaff’s Rule Adenine must pair with Thymine
Guanine must pair with Cytosine
Their amounts in a given DNA molecule will be about the same. T A G C

10. Humans share 50% of their DNA with bananas.
Cells can contain 6-9 feet of DNA. If all the DNA in your body was put end to end, it would reach to the sun and back over 600 times.
DNA in all humans is 99.9 percent identical. It is about one tenth of one percent that makes us all unique, or about 3 million nucleotides difference.
DNA can store 25 gigabytes of information per inch and is the most efficient storage system known to human. So, humans are better than computers!!
In an average meal, you eat approximately 55,000,000 cells or between 63,000 to 93,000 miles of DNA.
It would take a person typing 60 words per minute, eight hours a day, around 50 years to type the human genome.

11. DNA Structure
To crack the genetic code found in DNA we need to look at the sequence of bases.
The bases are arranged in triplets called codons.
A G G - C T C - A A G - T C C - T A G
T C C - G A G - T T C - A G G - A T C

12. DNA Structure A gene is a section of DNA that codes for a protein.
Each unique gene has a unique sequence of bases.
This unique sequence of bases will code for the production of a unique protein.
It is these proteins and combination of proteins that give us a unique phenotype.

13. DNA
Gene
Protein
Trait

14. Your Task
Draw a flow chart to show how to get from:

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