News tagged with algae
Related topics: biofuel , coral reefs , photosynthesis , carbon dioxide , bacteria
Algae (pronounced /ˈældʒiː/; singular alga /ˈælɡə/, Latin for "seaweed") are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms. The largest and most complex marine forms are called seaweeds. They are photosynthetic, like plants, and "simple" because they lack the many distinct organs found in land plants. For that reason they are currently excluded from being considered plants.
Though the prokaryotic Cyanobacteria (commonly referred to as Blue-green Algae) were traditionally included as "Algae" in older textbooks, many modern sources regard this as outdated and restrict the term Algae to eukaryotic organisms. All true algae therefore have a nucleus enclosed within a membrane and chloroplasts bound in one or more membranes. Algae constitute a paraphyletic and polyphyletic group, as they do not include all the descendants of the last universal ancestor nor do they all descend from a common algal ancestor, although their chloroplasts seem to have a single origin.
Algae lack the various structures that characterize land plants, such as phyllids and rhizoids in nonvascular plants, or leaves, roots, and other organs that are found in tracheophytes. Many are photoautotrophic, although some groups contain members that are mixotrophic, deriving energy both from photosynthesis and uptake of organic carbon either by osmotrophy, myzotrophy, or phagotrophy. Some unicellular species rely entirely on external energy sources and have limited or no photosynthetic apparatus.
Nearly all algae have photosynthetic machinery ultimately derived from the Cyanobacteria, and so produce oxygen as a by-product of photosynthesis, unlike other photosynthetic bacteria such as purple and green sulfur bacteria. Fossilized filamentous algae from the Vindhya basin have been dating back to 1.6 to 1.7 billion years ago.
The first alga to have its genome sequenced was Cyanidioschyzon merolae.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
(HealthDay)—People who eat large, tropical predatory reef fish such as barracuda and grouper may be at risk for a form of food poisoning called ciguatera fish poisoning, U.S. health officials reported Thursday.
Health Jan 31, 2013 | not rated yet | 0
(AP)—A federal inspector found two strains of salmonella and unclean conditions at an Indiana cantaloupe farm's fruit-packing plant during visits following a deadly outbreak linked to its melons.
Diseases, Conditions, Syndromes Oct 03, 2012 | not rated yet | 0
(Phys.org)—A team of international marine scientists has reported a 60 per cent increase in the incidence of cases of Ciguatera poisoning among people living in Pacific Island nations.
Diseases, Conditions, Syndromes Sep 11, 2012 | not rated yet | 0 |
A new research project conducted at the Faculty of Life Sciences (LIFE), University of Copenhagen, shows that dietary fibres from brown algae boost the sensation of satiety, thereby making people eat less and lose more weight.
Health Dec 08, 2011 | 5 / 5 (1) | 0
(Medical Xpress) -- Warning signs have been showing up all summer: Several lakes and ponds in Kansas have been reporting contamination from toxic blue-green algae.
Health Sep 02, 2011 | 4 / 5 (2) | 0
Scientists have for years been puzzled by why drugs are sometimes effective in treating parasitic diseases, while other times they have little or no effect.
Medical research Jun 21, 2011 | not rated yet | 0 |
(PhysOrg.com) -- The song about three blind mice may just be a song of the past according to new research presented by neuroscientist Alan Horsager from the Institute of Genetic Medicine at the University of Southern California ...
Medical research Apr 15, 2011 | 4.6 / 5 (8) | 1 |