Genes - Module 1 Reading / Watching

Genes are the basic unit of inheritance containing the information for physical and biological traits. They contain the information necessary for living cells to survive and reproduce . Genes are regions of the DNA .They are passed from parents to offspring. They code for specific proteins or segments of proteins. Humans have approximately 20,000 protein coding genes . These  20,000 protein coding genes are encoded only 1.5% of the entire human genome. Not all genes code only for proteins , some genes encode information for making an RNA molecule that functions other than directly coding for a protein.

Genes in genome of eukaryotes consist of exons and introns. Exons are the protein coding regions of mRNA. These are the regions that contain information for making a protein whereas other regions of the RNA are non-coding and these regions are called introns

The majority of human genes have two or more possible alleles, which are alternative forms of a gene. Differences in alleles account for the considerable genetic variation among people. In fact, most human genetic variation is the result of differences in individual DNA bases within alleles.