Organic Chemistry Test

The chemical compound acetylcholine is a neurotransmitter in both the peripheral nervous system (PNS) and central nervous system (CNS) in many organisms including humans. Acetylcholine is one of many neurotransmitters in the autonomic nervous system (ANS) and the only neurotransmitter used in the motor division of the somatic nervous system.

Asparagine is one of the 20 most common natural amino acids on Earth. It has carboxamide as the side-chain's functional group. It is a nonessential amino acid. Its codons are AAU and AAC.

Polycarbonates are transparent, self-extinguishing materials. They possess properties like crystalline thermoplasticity, high impact strength, good thermal and oxidative stability. They can be used in machinery, auto-industry and medical applications. For example, the cockpit canopy of F-22 Raptor is made of high optical quality polycarbonate.

Ribitol is a crystalline pentose alcohol formed by the reduction of ribose. It occurs naturally in the plant Adonis vernalis, as well as in the cell walls of Gram positive bacteria .It also contributes to the chemical structure of riboflavin.

Methyl orange is a pH indicator frequently used in titrations because of its clear colour change. As it changes colour at the pH of a mid-strength acid, it is usually used in titrations for acids.

Ornithine is an amino acid that plays a role in the urea cycle. L-Ornithine is one of the products of the action of the enzyme arginase on L-arginine, creating urea. Therefore, ornithine is a central part of the urea cycle, which allows for the disposal of excess nitrogen.

Alcian blue stain – used to stain cartilage. Cheapest form available works fine.

Tyrosine is one of the 20 amino acids that are used by cells to synthesize proteins. Its codons are UAC and UAU. It is a non-essential amino acid with a polar side group.

Glutamic acid is one of the 20 proteinogenic amino acids, and its codons are GAA and GAG. It is a non-essential amino acid. The carboxylate anions and salts of glutamic acid are known as glutamates. In neuroscience, glutamate is an important neurotransmitter that plays a key role in long-term potentiation and is important for learning and memory.

Tryptophan is one of the 20 standard amino acids, as well as an essential amino acid in the human diet. It is encoded in the standard genetic code as codon UGG.

A polyamide is a polymer containing monomers of amides joined by peptide bonds. They can occur both naturally and artificially, examples being proteins, wool and silk, and can be made artificially through step-growth polymerization or solid-phase synthesis, examples being nylons, aramids, and sodium poly(aspartate).

Aromatic polyimide are synthesized by the reaction of dianhydrides with diamines, for example, pyromellitic anhydride with ''p''-phenylenediamine. It can also be accomplished using diisocyanates in place of diamines.

Sudan II (C₁₈H₁₆N₂O) is a lysochrome (fat-soluble dye) azo dye used for staining of triglycerides in frozen sections, and some protein bound lipids, and lipoproteins on paraffin sections. It has the appearance of red powder with melting point 156-158 °C and maximum absorption at 493(420) nm.

Polysaccharides are polymeric carbohydrate structures, formed of repeating units (either mono- or di-saccharides) joined together by glycosidic bonds. These structures are often linear, but may contain various degrees of branching. Polysaccharides are often quite heterogeneous, containing slight modifications of the repeating unit.

Styrene-Butadiene or Styrene-Butadiene-Rubber (SBR) is a synthetic rubber copolymer consisting of styrene and butadiene. It has good abrasion resistance and good aging stability when protected by additives, and is widely used in car tyres, where it may be blended with natural rubber.

Chitin is a long-chain polymer of a N-acetylglucosamine, a derivative of glucose, and is found in many places throughout the natural world. It is the main component of the cell walls of fungi, the exoskeletons of arthropods such as crustaceans (e.g., crabs, lobsters and shrimps) and insects, the radulas of mollusks, and the beaks of cephalopods, including squid and octopuses.

These proteins contain energy, which can be released during metabolism processes in the organism. Egg ovalbumin and milk casein are such proteins. Almost all proteins can be digested and used as a source of energy and building material by other organisms.

Cross-linked polyethylene, is a form of polyethylene with cross-links. It is formed into tubing, and is used predominantly in hydronic radiant heating systems, domestic water piping and insulation for high tension (high voltage) electrical cables. It is also used for natural gas and offshore oil applications,  transportation of chemicals, and transportation of sewage and slurries.

Isoleucine is necessary for the optimal growth of infants and for nitrogen balance in adults.

L-carnosine supports healthy ageing and cellular rejuvenation by its effects on two mechanisms: glycosylation and free radical damage.

Alanine is necessary for the promotion of proper blood glucose levels from dietary protein. It stimulates lymphocyte production and may help people who have immune suppression. It also strengthens the immune system by producing antibodies.

Serine is needed for the metabolism of fats and fatty acids, muscle growth and a healthy immune system.

Tryptophan is important for the production of serotonin. Increasing tryptophan may help to normalize sleep patterns.

Polyacrylonitrile (PAN) is a resinous, fibrous, or rubbery organic polymer. PAN fibres are the chemical precursor of high-quality carbon fibre. It is chemically modified to make the carbon fibres found in plenty of both high-tech and common daily applications such as civil and military aircrafts,  primary and secondary structures, missiles, solid propellant rocket motors, pressure vessels, fishing rods, tennis rackets, badminton rackets and high-tech bicycles.

All are proteins.

Cysteine strengthens the protective lining of the stomach and intestines, which may help prevent damage caused by aspirin and similar drugs.

Congo red is a secondary diazo dye. Congo red is water soluble, yielding a red colloidal solution; its solubility is better in organic solvents such as ethanol. It has a strong, though apparently non-covalent affinity to cellulose fibres.

One of the main conformational parameter of the amino acid structure is the value of the PHI and PSI angles. These angles completely define the conformation of the polypeptide chain. With some special values for these angles the main chain can adopt specially classified conformations, like alpha-helix or beta-strand. The other main feature of the protein secondary structure is the local stabilisation by hydrogen bonds. These conformations are classified as a protein secondary structure.