Cell division is the process by which a cell, called the parent cell, divides into two cells, called daughter cells. When the cell divides, everything inside it divides also. The nucleus and the chromosomes divide, and the mitochondria divide also.
In mitosis, an ordinary body (somatic) cell divides to make two daughter cells.
In meiosis, a cell divides twice, to produce four gametes (sex cells). The first division of meiosis is a special kind of cell division called a reduction division because the number of chromosomes is halved. The second division of meiosis is similar to mitosis.
Cells are the 'building blocks' of life, and cell division is a basic feature of life. For simple unicellular organisms like Amoebozoa, one cell division reproduces the entire organism. On a larger scale, cell division can create offspring from multicellular organisms, such as plants that grow from cuttings. But most importantly, cell division enables organisms that are able to sexually reproduce to develop from the one-celled fertilised egg (zygote). Cell division also allows for continual renewal and repair of the organism.
Saparmurat Niyazov
Saparmurat Niyazov (February 19, 1940 - December 21, 2006) was the first President of Turkmenistan. He served from 1993 to 2006. Saparmurat Niyazov also called himself Türkmenbaşy, which means leader of the Turkmen people. He tried to make a cult of personality, which means that he put many pictures and statues of himself around his country to make himself seem important. While he was president, Niyazov made doing many things against the law, such as growing a beard or ballet dancing. He died from a heart attack on December 21, 2006, and Gurbanguly Berdimuhammedow became the new president of Turkmenistan.
Spruce (disambiguation)
Spruce are trees in the genus "Picea". "Spruce" may also mean:
Places:
People:
Temperate zone
In geography, temperate latitudes of the Earth lie between the subtropics and the polar circles. Average yearly temperatures in these regions are not extreme, not burning hot nor freezing cold. Temperate means moderate.
Unlike in the tropics, temperatures can change greatly here, between summer and winter. So, most places with a temperate climate have four seasons: summer, autumn, winter and spring. Other areas with a temperate climate can have very unpredictable weather. One day it may be sunny, the next may be rainy, and after that it may be cloudy. This is normal in summer as well as in winter. These are the main types of temperate climate:
Lithuanian language
The Lithuanian language is a Baltic language. It is from Lithuania, spoken in a few countries in Europe, as well as in the Americas and Australia.
Lithuanian and Latvian are the only remaining Baltic languages. Both languages have much in common. Lithuanian, however, adopted fewer words and phrases from German and other languages. However, many words were adopted into Lithuanian by Slavic languages long ago, but in 1920, Lithuanian philologist Jonas Jablonskis and others replaced them with native Lithuanian words..
There are two main dialects of Lithuanian. "Samogitian" is used mostly in West Lithuania, and the other that is widely used in the whole country is "Aukštaitian" (Highlanders' dialect). The standard Lithuanian comes from West Aukštaitian.
The first book written in Lithuanian is "Katekizmas" by Martynas Mažvydas. It was published in East Prussia in 1547.
Depeche Mode
Depeche Mode is an English band. It formed in Basildon, Essex in 1980. The band's name was taken from French fashion magazine, "Dépêche mode", which means "fashion update" or "fashion news dispatch". Depeche Mode became famous in the 1980s. The band has sold over 100 million records around the world.
Depeche Mode were inducted into the Rock and Roll Hall of Fame in 2020.
Depeche Mode has three members:
Gingivitis
Gingivitis is the inflammation of the gums around the teeth. Gingivitis may be caused by a buildup of plaque and tartar because the teeth have not been cleaned properly. It can also be a manifestation of a systemic disease, as in diabetes or AIDS.
Sometimes excessive brushing or flossing can wear out the gums causing gum recession.
If gingivitis is not treated by proper oral hygiene, it can lead to periodontitis, which is a more advanced state of gum disease, that affects the bone and is harder to treat.
Taiga
The taiga is a large area of coniferous forests. It covers most of inland Alaska, Canada, Sweden, Finland, inland Norway, northern Kazakhstan and Russia (especially Siberia), as well as parts of the northern continental United States.
In Canada, boreal forest is the term used to refer to the southern part of these forests, while "taiga" is used to describe the northern areas south of the Arctic tree line that separates it from tundra.
The trees are mostly pines, spruces and larches. The climate is cold winters and cool summers.
Conifer
The Conifers are cone-bearing seed plants. Most are trees; some are shrubs. They are formally the Division Pinophyta or Coniferophyta.
Conifers are Gymnosperms. They are cone-bearing seed plants with vascular tissue. All living conifers are woody plants, and most are trees.
Living conifers are all in the order Pinales. Typical examples include cedars, cypresses, firs, junipers, kauris, larches, pines, redwoods, spruces, and yews.
Species of conifers can be found in almost all parts of the world, and are often the most common plants in their habitats, as in the taiga. Conifers are of great economic value, and their wood is mainly used for timber and paper making. The wood of conifers is known as softwood, though yew wood is actually quite hard. The division "Coniferae" contains about 700 living species.
The earliest conifers were in the late Carboniferous (Pennsylvanian) period (about 300 million years ago), Pinophytes, Cycads, and Ginkgos all developed at this time. These plants live without being so dependent on water. Other adaptations are pollen (so Fertilization can occur without water) and the seed, which allows the embryo to be transported and developed elsewhere.
Conifers appear to be one of the taxa that benefited from the Permian–Triassic extinction event. They were the dominant land plants of the Mesozoic era. Conifers were eventually overtaken by the flowering plants, which first appeared in the Cretaceous. Flowering plants became dominant in the Cainozoic era.
Conifers were the main food of herbivorous dinosaurs, and their resins and poisons no doubt gave them some protection against herbivores. All the reproductive features of modern conifers had evolved by the end of the Mesozoic era.
Binomial nomenclature
In biology, binomial nomenclature is how species are named. The name of a species is made of two parts: one indicating the genus and one indicating the species. Binomial nomenclature means "two-part name" or "system of two-part names".
The person who popularized this system for use was Swedish botanist and physician Carolus Linnaeus (1707–1778). He gave a two-part name to every species he knew. This kind of naming had been used before Linnaeus by some naturalists, but after Linnaeus, it was accepted as a good method.
The value of the binomial nomenclature comes from several things. It saves words because it replaces long descriptions, it is used everywhere, and the names are unique and stable. The system ended the use of local common names, which was the source of much confusion. When science was done by just a few European countries their common names for species were well-known. But as it happened, the common names in all countries was rather different. The same name might be used for more than one species, and several species given the same name. In the Linnaeus system, everyone uses the same name for the same species. Linnaeus chose Latin names: first, because it avoided competitive nationalism; second, because most educated people in his day learned Latin.