Modelau 3D Bacteria

Yn dangos yr holl ganlyniadau 5

Bacteria yw parth micro-organebau procaryotig. Fel arfer mae gan facteria sawl micron o hyd, gall eu celloedd fod â siâp amrywiol: o sfferig i siâp gwialen a siâp troellog.

Bacteria is one of the first forms of life on Earth and occurs in almost all terrestrial habitats. They inhabit the soil, fresh and marine reservoirs, sour hot springs, radioactive waste and deep layers of the earth’s crust. Bacteria are often symbionts and parasites of plants and animals. Most bacteria are not described to date, and representatives of only half of the bacterial types can be grown in the laboratory. Bacteria are studying the science of bacteriology – a section of microbiology.

Mae un gram o bridd, ar gyfartaledd, yn cynnwys celloedd bacteriol 40 miliwn, ac mewn mililitr o ddŵr ffres gall un ddod o hyd i filiwn o gelloedd bacteria. Ar y Ddaear mae tua 5 × bacteria 1030 ac mae eu biomas yn uwch na chyfanswm biomas anifeiliaid a phlanhigion. Maent yn chwarae rhan bwysig yn nosbarthiad maetholion, er enghraifft, y bacteria sy'n gosod nitrogen atmosfferig. Maent hefyd yn dadelfennu gweddillion anifeiliaid a phlanhigion trwy bydru. Mae bacteria eithafol, sy'n byw ger ffynonellau oer a hydrothermol poeth, yn cynhyrchu ynni o gyfansoddion anhydawdd fel hydrogen sylffid a methan. Tybir bod y bacteria hefyd yn byw ym Marvity Mariana, gyda dyfnder o 11 cilomedr. Mae adroddiadau o facteria sy'n byw mewn creigiau caregog 580 metr yn ddwfn islaw gwely'r môr ar ddyfnder o 2.6 cilometr ger gogledd-ddwyrain yr Unol Daleithiau.

The human microflora is 39 trillion bacterial cells (the human body itself consists of about 30 trillion cells). The most numerous intestinal microflora, the skin is also inhabited by many bacteria. Most bacteria living in the human body are harmless due to the immune system’s containment, and some even benefit. A number of bacteria are pathogenic to humans. Infectious diseases such as cholera, syphilis, anthrax, leprosy and bubonic plague are caused by bacteria. The largest number of deaths is caused by bacterial respiratory infections, and only tuberculosis kills 2 million people a year (mainly in sub-Saharan Africa). In developed countries antibiotics are used not only for the treatment of human diseases, but also in livestock breeding, due to which the problem of resistance to antibiotics is becoming more and more relevant. In the industry, bacteria are used in the treatment of sewage, to eliminate oil spills, to obtain cheese and yogurt, to restore gold, palladium, copper and other metals from ores, as well as in biotechnology, to produce antibiotics and other compounds.