UNDERSTANDING DNANOTES

Structure of DNA

• DNA = Deoxyribonucleic acid

• Made out of sugars (deoxyribose), phosphates

and nitrogen bases

Double Helix polymer

This is a nucleotide

Nucleotides

• What is a nucleotide?• Three parts:• 1)Phosphate,• 2)sugar, • 3)nitrogen base.

H

A,T,G and C - The letters of life

Adenine Thymine

Guanine Cytosine

If you were to start reciting the order of the ATCGs in your DNA tomorrow morning, at a rate of 100 each minute, 57 years would pass before you reached the end…

Base Pairing

A pairs with T & C pairs with G

Triplet

The code within DNA is based on a triplet system…

CCC CCA CCT CCGCAC CAA CAT CAG

DNA codes in three letter words……

All the different possible combos of triplets (also called codons)

DNA Replication• Making copies of DNA

– Because the bases always pair up, guanine with cytosine, and thymine with adenine, the bases on one side of the molecule form a pattern for the other side.

– The molecule splits and the corresponding bases pair up to form two new molecules.

– A pairs with ? G pairs with ? T pairs with ? C pairs with ?– AGTTGCAAGTCTAC– ?????????????????????

Dna Replication

http://www.youtube.com/watch?v=hfZ8o9D1tus

DNA replication

What is a gene?

A human chromosome has thousands of genesEach gene is a recipe for a protein!

Chromosomes

Genome

Collection of genetic

information within all

genes contained in

the DNA molecule(s)

in a cell.

If the genome was a book, it would be the equivalent of 800 dictionaries. It would take a person typing 60 words per minute, eight hours a day, around 50 years to type the human genome.