Nanogram (ng )

- A measurement of weight. There are one thousand nanograms in one microgram.

Nucleic Acid Sequence Based Amplification ( NASBA )

-  NASBA is an isothermal nucleic acid amplification procedure based on target-specific primers and probes, and the coordinated activity of THREE enzymes: AMV reverse transcriptase, RNase H and T7 RNA polymerase. NASBA allows direct detection of viral RNA by nucleic acid amplification.
Definition from:
http://dorakmt.tripod.com/genetics/glosrt.html
 

Nested PCR

-  Nested PCR is a conventional PCR with a second round of amplification using a different set of primers. This second set of primers is specific to a sequence found within the DNA of the initial conventional PCR amplicon. The use of a second amplification step with the "nested" primer set results in a reduced background from products amplified during the initial PCR due to the nested primers’ additional specificity to the region. The amount of amplicon produced is increased as a result of the second round of amplification and due to a reduction in any inhibitor concentrations.
Definition from:
Quality Assurance/Quality Control Guidance for Laboratories Performing PCR Analyses on Environmental Samples

-  A very sensitive method for amplfication of DNA, which takes part of the product of a single PCR reaction (after 30-35 cycles), and subjects it to a new round of PCR using a different set of PCR primers which are nested within the region flanked by the original primer pair
Definition from:
http://www.med.unc.edu/wrkunits/3ctrpgm/pmbb/mbt/GLOS.htm

-  A second PCR is performed on the product of an earlier PCR using primers which are internal to the originals. This improves sensitivity without impairing specificity
Definition from:
http://www.lshtm.ac.uk/pmbu/staff/rmcnerney/homepage/glossary.html

-  The second round amplification of an already PCR-amplified sequence using a new pair of primers which are internal to the original primers. Typically done when a single PCR reaction generates insufficient amounts of product.
Definition from:
Bioinformatics Glossary

Nucleic acid

-  DNA or RNA. Each of these compounds consists of a backbone of sugar molecules ribose for RNA and deoxyribose for DNA linked by single phosphate groups. Attached to the sugars of the backbone are any of four nitrogenous bases, A, T, C or G for DNA and A, U, C or G for RNA.
Definition from:
Mouse Genome Informatics

-  Nucleic acids are biochemical macromolecules that are composed of nucleotide chains, the genetic building blocks of life. DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) are the most well known types of nucleic acid, and are found in living cells and viruses.
Definition from:
ISCID

-  A large molecule composed of nucleotide subunits.
Definition from:
Genome Glossary

Nucleotide
-  The monomer units that are used to make up the DNA molecule. Each has one of the four bases, A, G, T, or C attached to a sugar phosphate that forms the backbone of the DNA polymer.
Definition from:
Genelex

-  A subunit of DNA or RNA consisting of a nitrogenous base (adenine, guanine, thymine, or cytosine in DNA; adenine, guanine, uracil, or cytosine in RNA), a phosphate molecule, and a sugar molecule (deoxyribose in DNA and ribose in RNA). Thousands of nucleotides are linked to form a DNA or RNA molecule
Definition from:
Genome Glossary

- Nucleotides are the single units that make up nucleic acids like RNA and DNA literally the building blocks of life.
Definition from:
ISCID