CHEMISTRY GLOSSARY

hydration    →   hidratacija

Hydration is addition of water or the elements of water (i.e. H and OH) to a molecular entity. The term is also used in a more restricted sense for the process:

isoleucine    →   izoleucin

Isoleucine is hydrophobic amino acids with aliphatic side chain. It is one of the three amino acids having branched hydrocarbon side chains. The side chains of these amino acids are not reactive but, these residues are critically important for ligand binding to proteins, and play central roles in protein stability. Isoleucine is an essential amino acid, which means that humans cannot synthesize it, so it must be ingested.

• Abbreviations: Ile, I
• IUPAC name: 2-amino-3-methylpentanoic acid
• Molecular formula: C₆H₁₃NO₂
• Molecular weight: 131.12 g/mol

surface tension    →   površinska napetost

Surface tension (σ) is a property of liquids arising from unbalanced molecular cohesive forces at or near the surface, as a result of which the surface tends to contract and has properties resembling those of a stretched elastic membrane. As a result of which the surface tends to contract and has properties resembling those of a stretched elastic membrane.

unified atomic mass unit    →   unificirana atomska jedinica mase

Unified atomic mass unit (u or m_u) is a unit of mass used in atomic, molecular, and nuclear science, defined as the mass of one atom of ¹²C divided by 12. Its approximate value is

leucine    →   leucin

Leucine is hydrophobic amino acids with aliphatic side chain. It has one additional methylene group in its side chain compared with valine. The nonpolar hydrophobic amino acids tend to cluster together within proteins, stabilizing protein structure by means of hydrophobic interactions. Leucine is an essential amino acid, which means that humans cannot synthesize it, so it must be ingested.

• Abbreviations: Leu, L
• IUPAC name: 2-amino-4-methylpentanoic acid
• Molecular formula: C₆H₁₃NO₂
• Molecular weight: 131.17 g/mol

liquid aggregate state    →   tekuće agregatno stanje

Liquids have a constant volume, but they do not have a constant shape. They assume the shape of a vessel they are in at the moment. It happens because molecules of liquids are still close enough to each other, the attracting forces still being very strong.

valence bond theory    →   teorija valentne veze

Valence bond theory is a theory that explains the shapes of molecules in terms of overlaps between half-filled atomic orbitals, or half filled hybridised orbitals.

VSEPR    →   VSEPR

Valence shell electron pair repulsion theory (VSEPR) is a model that explains the shapes of molecules by assuming that electron pairs arrange themselves around atoms in a way that minimizes electron-electron repulsions.

lysine    →   lizin

Lysine is an electrically charged amino acids with basic side chains. Lysine is a base, as are arginine and histidine. The amino group is highly reactive and often participates in reactions at the active centers of enzymes. Lysine plays an important role in coordinating negatively charged ligands. It is an essential amino acid, which means that humans cannot synthesize it, so it must be ingested.

• Abbreviations: Lys, K
• IUPAC name: 2,6-diaminohexanoic acid
• Molecular formula: C₆H₁₄N₂O₂
• Molecular weight: 146.19 g/mol

macromolecule    →   makromolekule

Macromolecule is a molecule of high relative molecular mass (molecular weight), the structure of which essentially comprises the multiple repetitions of units derived, actually or conceptually, from molecules of low relative molecular mass. The types of macromolecules are natural and synthetic polymers, carbohydrates, lipids, proteins etc. Cellulose is a polysaccharide that is made up of hundreds, even thousands of glucose molecules strung together.