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A protein is a polyamide. Secondary structure: regularly repeating local structures stabilized by hydrogen bonds. The most common examples are the α-helix, β-sheet and turns. Because secondary structures are local, many regions of different secondary structure can be present in the same protein molecule.
Structure of a typical L-alpha-amino acid in the "neutral" form Amino acids are organic compounds that contain both amino and carboxylic acid functional groups.[1] Although over 500 amino acids exist in nature, by far the most important are the 22 α-amino acids incorporated into proteins.[2] Only these 22 appear in the genetic code of life.[3 ...
Viviparus georgianus, commonly known as the banded mystery snail, is a species of large freshwater snail in the family Viviparidae, the river snails. It is native to North America, generally found from the northeastern United States to Florida and the Gulf of Mexico, and thrives in eutrophic lentic environments such as lakes, ponds and some low ...
Wireless LAN (WLAN) channels are frequently accessed using IEEE 802.11 protocols. The 802.11 standard provides several radio frequency bands for use in Wi-Fi communications, each divided into a multitude of channels numbered at 5 MHz spacing (except in the 45/60 GHz band, where they are 0.54/1.08/2.16 GHz apart) between the centre frequency of the channel.
A glass of cow milk. Cows in a rotary milking parlor. Milk is a white liquid food produced by the mammary glands of mammals and the caecilian Siphonops annulatus. [1] It is the primary source of nutrition for young mammals (including breastfed human infants) before they are able to digest solid food. [2]
0.8–1.5% (2019, using DSM-IV-TR and ICD-10) [2] Attention deficit hyperactivity disorder ( ADHD) is a neurodevelopmental disorder characterised by executive dysfunction occasioning symptoms of inattention, hyperactivity, impulsivity and emotional dysregulation that are excessive and pervasive, impairing in multiple contexts, and otherwise age ...
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 ...
