Genes are linear sequences of DNA polymer.
Heritable information is stored in these DNA sequences.
A linear sequence is a codon.
The codon may be small or large, have a few subregions or many subregions.
A series of nucleotides can be put together without forming a gene (non-coding regions of DNA).
Each gene codes for a cellular process or function.
Genes act in combination with an organism's environment to influence development.
sequences, LINEs, SINEs, introns, and sequences for which as yet no function has been elucidated.[4]
1. Number of Chromosomes
2. Sequence of human genome
Human genetic information primarily is contained within chromosomal nuclear genes, inherited from both parents, but is also present in mitochondrial genes inherited from the maternal line. (New data says it is also inherited from the fraternal line.
There are an estimated 20,000-25,000 human protein-coding genes. Protein-coding sequences account for only a very small fraction of the genome (approximately 1.5%), and the rest is associated with non-coding RNA molecules, regulatory DNA