What is DNA?• DNA is a molecule that

contains ALL of an organism’s genetic material and is therefore responsible for HEREDITY

• A strand of DNA contains many GENES all of which code for PROTEINS

• Each of these proteins has a different function in a cell

Two scientists, James Watson and Francis Crick, were the first to discover the structure of DNA

They referred to it as a DOUBLE HELIX because it contains two complementary

strands, each of which is shaped like a spiral staircase

DNA stands for Deoxyribonucleic

Acid

DNA is made up of 3 main components:

Deoxyribose – a sugar molecule

Phosphates – which make up part of the backbone

Nitrogenous bases – Thymine, Adenine, Guanine, Cytosine

Where is DNA found?

How can we extract DNA from a cell?

DETERGENT (or soap) is used to LYSE (cut

up) the cell membrane.

Sodium Chloride = NaCl

The salt binds to the phosphate groups on the DNA strand and causes many DNA molecules to bind together

Ethanol (a type of alcohol) is used in DNA extraction. It

forces the DNA to PRECIPITATE out of the

solution

When alcohol is added to your DNA solution, you will notice that 2 separate layers form. The place where these two layers meet is called the INTERFACE

The interface is where you will be able to find the DNA you have extracted