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

DNA replication - start at 3:53

What is a gene?

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

Chromosomes

Genome

Genome: Collection of genetic information within all genes contained in the DNA molecule(s) in a cell.

If the genome was written out in book form, it would be the equivalent of 4,000 books. It would take a person typing 60 words per minute, eight hours a day, around 50 years to type the human genome.

If all the DNA in one of your cells were uncoiled, connected, and stretched out, it would be about 6 feet long. It would be so thin its details could not be seen, even under an electron microscope. If all this very densely coded information from one cell of one person were written in books, it would fill a library of about 4,000 books. If all the DNA in your body were placed end-to-end, it would stretch from here to the Moon more than 500,000 times! In book form, that information would fill the Grand Canyon almost 100 times. If one set of DNA (one cell’s worth) from every person who ever lived were placed in a pile, the final pile would weigh less than an aspirin.