Portal:Biology
Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of at least one cell that processes hereditary information encoded in genes, which can be transmitted to future generations. Another major theme is evolution, which explains the unity and diversity of life. Energy processing is also important to life as it allows organisms to move, grow, and reproduce. Finally, all organisms are able to regulate their own internal environments. (Full article...)
Selected article -
A virus is a tiny infectious agent that reproduces inside the cells of living hosts. When infected, the host cell is forced to rapidly produce thousands of identical copies of the original virus. Unlike most living things, viruses do not have cells that divide; new viruses assemble in the infected host cell. But unlike simpler infectious agents like prions, they contain genes, which allow them to mutate and evolve. Over 4,800 species of viruses have been described in detail out of the millions in the environment. Their origin is unclear: some may have evolved from plasmids—pieces of DNA that can move between cells—while others may have evolved from bacteria.
Viruses are made of either two or three parts. All include genes. These genes contain the encoded biological information of the virus and are built from either DNA or RNA. All viruses are also covered with a protein coat to protect the genes. Some viruses may also have an envelope of fat-like substance that covers the protein coat, and makes them vulnerable to soap. A virus with this "viral envelope" uses it—along with specific receptors—to enter a new host cell. Viruses vary in shape from the simple helical and icosahedral to more complex structures. Viruses range in size from 20 to 300 nanometres; it would take 33,000 to 500,000 of them, side by side, to stretch to 1 centimetre (0.4 in). (Full article...)
Selected picture -
Chimaeras are cartilaginous fish in the order Chimaeriformes, known informally as ghost sharks, ratfish, spookfish, or rabbitfishes. They grow up to 150 cm (4.9 ft) in length, and have elongated, soft bodies, with a bulky head and a single gill-opening. For defense, most chimaeras have a venomous spine located in front of the dorsal fin. At one time a "diverse and abundant" group (based on the fossil record), their closest living relatives are sharks, though in evolutionary terms they branched off from sharks nearly 400 million years ago and have remained isolated ever since, typically confined to deep water.
Major topics
Selected biography -
Francis Harry Compton Crick OM FRS (8 June 1916 – 28 July 2004) was an English molecular biologist, biophysicist, and neuroscientist. He, James Watson, Rosalind Franklin, and Maurice Wilkins played crucial roles in deciphering the helical structure of the DNA molecule.
Crick and Watson's paper in Nature in 1953 laid the groundwork for understanding DNA structure and functions. Together with Maurice Wilkins, they were jointly awarded the 1962 Nobel Prize in Physiology or Medicine "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material". (Full article...)
General images -
Did you know -
- ... that one of the smallest fish, the Philippine goby, can only grow between 1 and 1.5 cm?
- ...that the largest flower, Rafflesia has a very foul odor?
- ... that mesoporous silica nanoparticles are prepared by the Stöber process and are used in preparing biosensors and delivering medications to within cellular structures?
Related portals
Categories
Anatomy - Anthropology - Astrobiology - Biochemistry - Bioengineering - Bioinformatics - Biotechnology - Botany - Cell biology - Conservation biology - Developmental biology - Ecology - Environmental science - Evolutionary biology - Genetics - Mathematical biology - Medicine - Microbiology - Immunology - Molecular biology - Mycology - Neuroscience - Paleontology - Palynology Parasitology - Pharmacology -
Phylogenetics - Physiology - Systems biology - Taxonomy - Toxicology - Virology - ZoologyMore topics
WikiProjects
WikiProjects connected with biology:
A complete list of scientific WikiProjects can be found here. See also Wikispecies, a Wikimedia project dedicated to classification of biological species.