Vocabulary
A relatively simple molecule which is used as a basic building block for the synthesis of a polymer; many polymers are joined together by covalent bonds to make the polymer, usually by condensation reactions; common examples include monosaccharides, amino acids and nucleotides
What are monomers?
A chemical bond, represented as —COO—, formed when an acid reacts with an alcoho
What is an ester bond / ester linkage?
The sequence of amino acids in a polypeptide or protein
What is a primary structure?
A polymer whose subunits are monosaccharides joined together by glycosidic bonds
What is a polysaccharide?
A helical structure formed by a polypeptide chain, held in place by hydrogen bonds; an ⍺-helix is an example of secondary structure in a protein
What is alpha-helix?
A test for the presence of reducing sugars; the unknown substance is heated with the reagent, and a change from a clear blue solution to the production of a yellow, red or brown precipitate indicates the presence of reducing sugars such as glucose
What is the Benedict's test?
The covalent bond joining neighboring amino acids together in proteins; it is a C–N link between two amino acid molecules, formed by a condensation reaction
What is a peptide bond?
The main structural protein of animals; known as ‘white fibers,’ the fundamental unit of the fiber consists of three helical polypeptide chains wound around each other, forming a “triple helix’ with high tensile strength
What is collagen?
Two forms of the same chemical compound such as alpha glucose and beta glucose
What is an isomer?
A protein whose molecules are folded into a relatively spherical shape, often has physiological roles and is often water-soluble and metabolically active, e.g. insulin, hemoglobin and enzymes
What is globular protein?
A test for the presence of amine groups and thus for the presence of protein; a reagent is added to the unknown substance, and a change from pale blue to purple indicates the presence of protein
What is the biuret test?
A giant molecule made from many similar repeating subunits joined together in a chain; the subunits are much smaller and simpler molecules known as monomers; examples of biological polymers are polysaccharides, proteins and nucleic acids.
What is a polymer?
Formed by the replacement of one of the fatty acid groups in triglyceride by an ionized phosphate group
What is a phospholipid?
A polysaccharide made from beta-glucose subunits; used as a strengthening material in plant cell walls
What is cellulose?
The three-dimensional arrangement of two or more polypeptides, or of a polypeptide and a non-protein component such as haem , in a protein molecule
What is quaternary structure?
A chemical reaction involving the joining together of two molecules by removal of a water molecule
What is condensation reaction?
A polysaccharide made of many glucose molecules linked together, that acts as a glucose stored in liver and muscle cells
What is glycogen?
A loose, sheet-like structure formed by hydrogen bonding between parallel polypeptide chains ; a 𝛽-pleated sheet is an example of secondary structure in a protein
What is beta-pleated sheet?
A type of lipid formed when three fatty acid molecules combine with glycerol, an alcohol with three hydroxyl (--OH) groups
What is a triglyceride?
The structure of a protein molecule resulting from the regular coiling or folding of the chain of amino acids (an ᾳhelix or 𝜷-pleated sheet)
What is secondary structure?
A C-O-C link between two sugar molecules, formed by a condensation reaction; it is a covalent bond.
What is glycosidic bond?
A relatively weak bond formed by the attraction between a group with a small positive charge on a hydrogen atom (Hᵟ+ ) and another group carrying a small negative charge ( ẟ- ), e.g. between two —Oẟ- Hᵟ+ groups
What is a hydrogen bond?
A chemical reaction in which a chemical bond is broken by the addition of a water molecule; commonly used to break down complex molecules into simpler molecules
What is hydrolysis?
Whose molecules have a relatively long, thin structure that is generally insoluble and metabolically inactive, and whose function is usually structural, e.g. keratin and collagen
What is fibrous protein?
The compact structure of a protein molecule resulting from the three-dimensional coiling of the chain of amino acids
What is tertiary structure?