Amino acids are any group of organic molecules that contain a basic amine group (NH2), a carboxylic acid group (COOH), and an organic group R (or called a side chain) that is unique to each amino acid and is the building block of proteins. The term amino acid is an abbreviation for αamino carboxylic acid. And each molecule contains a central carbon (C) atom, called alpha carbon, so that both groups are bound; The amine and the carboxylate. And the remaining two bonds of the alpha carbon will combine with a hydrogen atom, and the group R will be as follows:
Amino acids differ from each other according to the specific chemical group, the R group.
Building blocks of proteins
Proteins are essential to sustain life on Earth. It produces many of the structural elements in the cell, and helps to connect cells with each other in tissues.
Some proteins act as contractile elements, making movement possible. Others are responsible for transporting essential materials from outside the cell to inside it. Proteins in the form of antibodies protect animals from disease and resist an intracellular attack (antivirals or interferon) against viruses that have escaped their elimination through antibodies and other immune system defenses. And a lot of hormones are proteins.
This conglomeration of the core tasks is reflected in an impressive array of well-known proteins that are distinguished from each other by size, shape and charge. And at the end of the nineteenth century, scientists discovered - despite the presence of many different types of proteins in nature - that proteins result from a process (hydrolysis, that is, splitting a compound by inserting water - hydrolysis), a class of simpler compounds, which is the building block of proteins, called amino acids.
The simplest amino acid is called glycine, and it is so called because of its sweet taste (glyco, meaning sugar). It was one of the first amino acids known, as it was isolated from the protein (gelatin) in 1820. In the mid-1950s, scientists clarified the relationship between proteins and genes, grouped together as 20 amino acids (called essential or common amino acids) as a building block All proteins. The most recent discovery (threonine) was in 1935.
Chirality
All amino acids are analog molecules except for glycine. They are found in inverse visual analog forms (called enantiomers), that is, their reverse image in a mirror. This might resemble the relationship between the right hand and the left hand.
One of the homologs is denoted by the symbol D and the other by the symbol L. It is important to know that almost all of the amino acids in proteins belong to the L-formation. This reflects the fact that the enzymes responsible for synthesizing proteins evolved to form the L homolog only. Some D-amino acids are found in probiotic organisms, specifically in the cell walls of bacteria and in many antibiotics, however these are not synthesized in the ribosome.
The faces and shapes of crystals
What are crystals Microscopic level Crystallization Science that studies crystallization crystallization rocks halite transparent sapphire and red sapphire
Crystals are usually distinguished by their shape, which consists of flat faces with sharp angles. These formal properties are not necessary for an object to be a crystal - as a crystal is scientifically defined by its atomic arrangement on the microscopic level, not its external shape (macroscopic).
Crystals with well-defined flat faces are called (Euhedral). As for crystals that do not have a clear exterior - this is because the body is made of a large number of crystals fused together into a solid polycrystalline - they are called (anhedral).
The flat faces (also called sides) of Euhedral crystals are oriented in a specific way depending on the atomic arrangement of the crystal, so the crystal is more stable. One of the oldest techniques in crystallography is to measure the three-dimensional orientations of a crystal's faces, and to use them to infer the atomic arrangement of a crystal.
The crystal habit is its visible exterior. This is determined by the crystal structure (which restricts the potential orientations of the face), chemical bonds within the crystal (some types of faces are more stable than others), and the conditions in which the crystal was formed.
Being in nature
Rocks
The largest concentration of crystals in Earth, by size and weight, is found in the Earth's bedrock. The size of the crystals found in rocks typically ranges from a fraction of a millimeter to several centimeters, although exceptionally large crystals are occasionally present.
The world's largest naturally occurring crystal is a beryl crystal found in Malakialina, Madagascar Universe 1999. It is 18 meters (59 ft) in diameter, 3.5 meters (11 ft) in diameter, and weighs 380,000 kg (840,000 lb).
Ice
Water ice in the form of snow or polar ice is a very common manifestation of crystalline materials on Earth. Single snowflakes are usually a single crystal, while ice cubes are objects with multiple crystal structures.
Organic crystals
Many organisms are able to produce crystals, such as the calcite produced by most mollusks or the hydroxylapatite in the case of vertebrates.
Crystallization
Crystallization is the process of forming a crystalline structure from a liquid or from substances dissolved in a liquid. Crystallization is a complex and widely studied field because, depending on conditions, a single liquid can crystallize into many different shapes. It can form a single crystal, with different possibilities with different impurities, defects and habitats.
Or an object with multiple crystal structures can form, with possibilities that vary with size, arrangement, and orientation. The final shape of a crystal is determined by the conditions in which the liquid crystallizes, such as the chemistry of the liquid, ambient pressure, temperature, and the speed at which all of these factors change.
Defects and blemishes
Each atom in an ideal crystal is arranged in a perfect repeating arrangement. But, in fact, most crystalline materials contain a variety of crystal defects, which are places where the crystal pattern breaks down. These defects may have a profound effect on the properties of the material.
Some examples of crystal defects include vacancy defects (an empty space that had to be filled by an atom), interstitial defects (an additional atom compressed in a place where it does not fit).
What are crystals Microscopic level Crystallization Science that studies crystallization crystallization rocks halite transparent sapphire and red sapphire
Another common type of crystal defect is an impurity, meaning that a "wrong" type of atom is present in a crystal. For example, an ideal diamond crystal would only contain carbon atoms, but a true crystal might contain a few boron atoms as well.
These boron impurities change the color of the diamond to a little blue. Likewise, the only difference between transparent sapphire and ruby red is the type of impurity present in the corundum crystal.
Crystallography
Crystallography is a science that studies the crystal structure (in other words, the atomic arrangement) of a crystal. One of the techniques widely used in crystallography is X-ray diffraction. Large numbers of known crystal structures have also been stored in crystal databases.
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