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In mammals and other animals, the vagina ( pl.: vaginas or vaginae) [1] is the elastic, muscular reproductive organ of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen. At the deep end, the cervix (neck of the ...
The axolotl ( / ˈæksəlɒtəl / ⓘ; from Classical Nahuatl: āxōlōtl [aːˈʃoːloːtɬ] ⓘ) ( Ambystoma mexicanum) [3] is a paedomorphic salamander closely related to the tiger salamander. [3] [4] [5] It is unusual among amphibians in that it reaches adulthood without undergoing metamorphosis. Instead of taking to the land, adults remain ...
In a DNA double helix, each type of nucleobase on one strand bonds with just one type of nucleobase on the other strand. This is called complementary base pairing.Purines form hydrogen bonds to pyrimidines, with adenine bonding only to thymine in two hydrogen bonds, and cytosine bonding only to guanine in three hydrogen bonds. . This arrangement of two nucleotides binding together across the ...
Sun. The Sun is the star at the center of the Solar System. It is a massive, nearly perfect sphere of hot plasma, [18] [19] heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light and infrared radiation with 10% at ultraviolet energies.
Ketamine is a dissociative anesthetic used medically for induction and maintenance of anesthesia. It is also used as a treatment for depression and pain management.[19] It is a novel compound that was derived from phencyclidine in 1962 in pursuit of a safer anesthetic with fewer hallucinogenic effects.[20][21] At anesthetic doses, ketamine ...
Editing display showing MediaWiki markup language. A wiki ( / ˈwɪki / ⓘ WI-kee) is a form of online hypertext publication that is collaboratively edited and managed by its own audience directly through a web browser. A typical wiki contains multiple pages that can either be edited by the public or limited to use within an organization for ...
It covers 1,972,550 km 2 (761,610 sq mi), [11] making it the world's 13th-largest country by area; with a population of almost 130 million, it is the 10th-most-populous country and the most populous Spanish-speaking country. [12] Mexico is organized as a federal constitutional republic comprising 31 states and Mexico City, its capital.
