HUMAN DNA
The Map of Life
Deoxyribonucleic acid (DNA) is the chemical inside the nucleus of all cells that carries the genetic instructions for making living organisms. A DNA molecule consists of two strands that wrap around each other to resemble a twisted ladder - a helix.
Four different bases are present in DNA, and they form pairs...the "rungs" in the DNA ladder: adenine (A)
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"Junk DNA" - is a term used for repeated sequences that do not code for proteins. They make up 80-90% of the human genome, and are basically a collective label for the portions of the DNA sequence of a chromosome or a genome for which no function has yet been identified. While much of this sequence may be an evolutionary artifact that serves no present-day purpose, some is believed to function in ways that are not currently understood. It is here that we have the most flexibility to enhance or design better structures.
Proteins - perform most life functions and make up the majority of cellular structures.
Chomosomes - the DNA in human genomes are arranged into 24 or 26 pairs of distinct chromosomes.
A few types of major chromosomal abnormalities, including missing or extra copies, or gross breaks and rejoinings (translocations), can be detected by microscopic examination. Most changes in DNA, however, are more subtle and require a closer analysis of the DNA molecule to find perhaps single-base differences.
Chromosome #14 and the location of the Alzheimer's 3 gene.
Genes are units of heredity typically encoded in a sequence that make up a long strand of DNA.
Base pairs form genes.
Genes, about 50 million to 250 million base pairs come together to form DNA
DNA is 'packaged' inside a chromosome.
In May 2006, Human Genome Project researchers announced the completion of the DNA sequence identification for the last of the 24 human chromosomes.
