IntroductionNucleic acids are

macromolecules made up of smaller nucleotide subunits.

They carry genetic information, form specific structures in a cell or carry out specific roles in a cell.

Found in all living things and viruses.*

The two most common are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).

StructureNucleotides consist of

A nitrogenous baseA pentose sugarA phosphate group*

DNAUsed primarily for the

carrying of hereditary information and the recipe for making proteins.

DNA contains four different types of nucleotides that differ in their nitrogenous base only.

The four bases are: Adenine, Guanine, Cytosine and Thymine.

DNAThe shape of DNA is

a double helix, where two nucleotide strands run anti-parallel to each other.

It looks like a twisted ladder where the sugar and phosphate groups make up the sides and the nitrogenous bases make up the rungs.

DNAThe nucleotides are

held together by two types of bonds.

Phosphodiester bonds link the phosphate group of one nucleotide to the sugar of an adjacent nucleotide along the side of the double helix.

The nitrogenous bases are held together by hydrogen bonds across a rung.

DNA

In DNA, Adenine will only bind with Thymine and Guanine will only bond with Cytosine based on the number of hydrogen bonds each can form.

A and T each form 2 while C and G each form 3.

RNAUnlike DNA, RNA is

single stranded and generally much shorter in length.

RNA uses nucleotides Adenine, Cytosine and Guanine, but instead of Thymine, it uses another pyrimidine, Uracil.

There are three different types of RNA. They all play important roles in protein synthesis.

mRNA1) Messenger RNA decodes the DNA code

(“protein recipe”) and takes it from the nucleus to the ribosome.

tRNA2) Transfer RNA

brings amino acids to the ribosome to be incorporated into the newly forming polypeptide chain.

rRNA3) Ribosomal RNA is what makes up the ribosomes,

where proteins are made in the cell.

Other Important Nucleic Acids Some other nucleic acids that we will encounter

include:1) Adenosine Triphosphate (ATP) which is the energy

currency of the cell.

2) NAD, FAD, GDP and NADP, which are high energy electron carrying molecules used in cellular respiration or photosynthesis.