The NCBI was "established in 1988 as a national resource for molecular biology information, NCBI creates public databases, conducts research in computational biology, develops software tools for analyzing genome data, and disseminates biomedical information - all for the better understanding of molecular processes affecting human health and disease." Their databases include GenBank, "an annotated collection of all publicly available DNA sequences, maintained by NIH. It also connects visitors to PubMed Central, the digital archive of life sciences journal literature developed by NCBI at the National Library of Medicine. Many other useful links to resources for molecular biology information can be found here.
As evidenced by NCBI above, the federal government produces many useful web resources related to the sciences. This page provides an annotated list of links for governmental websites related to biology and nature. Browse the links, or use the Science.gov search engine to find specific materials in their 47 million webpages.
This free information portal published by Nature Publishing Group currently focuses on genetics, providing some free papers, an introduction to genetics, and discussion groups. The website is attractive and easy to navigate.