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On a larger scale, mitotic cell division can create progeny from multicellular organisms, such as plants that grow from cuttings. Mitotic cell division enables sexually reproducing organisms to develop from the one-celled zygote, which itself is produced by fusion of two gametes, each having been produced by meiotic cell division.
The function of astral microtubules can be generally considered as determination of cell geometry. They are absolutely required for correct positioning and orientation of the mitotic spindle apparatus , and are thus involved in determining the cell division site based on the geometry and polarity of the cells.
Amines can be formed by the reaction of ammonia with alkyl halides or, more commonly, with alcohols: CH 3 OH + NH 3 → CH 3 NH 2 + H 2 O. Its ring-opening reaction with ethylene oxide give ethanolamine, diethanolamine, and triethanolamine. Amides can be prepared by the reaction of ammonia with carboxylic acid and their derivatives.
In aqueous solution, ammonia deprotonates a small fraction of the water to give ammonium and hydroxide according to the following equilibrium: . NH 3 + H 2 O ⇌ NH + 4 + OH −.. In a 1 M ammonia solution, about 0.42% of the ammonia is converted to ammonium, equivalent to pH = 11.63 because [NH +
The hydrogen atoms in the ammonium ion can be substituted with an alkyl group or some other organic group to form a substituted ammonium ion (IUPAC nomenclature: aminium ion). Depending on the number of organic groups, the ammonium cation is called a primary, secondary, tertiary, or quaternary. Except the quaternary ammonium cations, the ...
The two isomers can be distinguished by UV-Vis spectroscopy. Absorbance maxima for the nitro isomer occur at 457.5, 325, and 239 nm. The nitrito has maxima at 486, 330, and 220 nm. [3] Their IR spectra also differ. The nitrito isomer absorbs at 1460 and 1065 cm −1. The nitro isomer absorbs at 1430 and 825 cm −1. [4]
Nitrogen can be fixed by lightning converting nitrogen gas (N 2) and oxygen gas (O 2) in the atmosphere into NO x (nitrogen oxides). The N 2 molecule is highly stable and nonreactive due to the triple bond between the nitrogen atoms. [75] Lightning produces enough energy and heat to break this bond [75] allowing nitrogen atoms to react with ...
Cell division orientation is one of the mechanisms that shapes tissue during development and morphogenesis. Along with cell shape changes, cell rearrangements, apoptosis and growth, oriented cell division modifies the geometry and topology of live tissue in order to create new organs and shape the organisms.