Cysteine
Lesson Flashcards: Structure of Proteins Biology
An amino acid that has a sulfhydryl group (–SH), which is a special functional group that can join together with another amino acid with a sulfhydryl group to form a disulfide group (–S–S–)
Enzyme
A biological catalyst that speeds up the rate of reactions without being used up
Alpha helix
A common structure in proteins in which a hydrogen bond is formed every fourth amino acid along a polypeptide chain, causing it to take a helical shape
Peptide bond
The chemical bond that forms between the amino and carboxyl groups of two amino acids
Collagen
The most abundant protein in mammals, which provides structure for connective tissues like ligaments and cartilage and for the skin
R group (side chain)
One of twenty different side chains of an amino acid that gives the amino acid its chemical properties
Actin and myosin
Two structural proteins that are important components of muscle cells
Condensation reaction (dehydration synthesis)
A chemical reaction in which a chemical bond is formed, causing a molecule of water to be released
Regulatory proteins
Proteins that regulate different processes and activities within an organism
Dimer
The complex formed by the association of two proteins
Polypeptide
A single linear chain of amino acids that are held together by peptide bonds, which can fold into a protein with a specific function
Amino acid
The monomers making up proteins, each of which containing a central carbon linked to an amino group, a carboxyl group, a hydrogen atom, and a side chain that varies between the 20 standard amino acids
Structural protein
The building materials of the body that provide structure to cells
Cytoskeleton
A complex network of interlinking protein filaments that gives the cell its shape and structure
Keratin
A type of structural protein that is found predominantly in hair, skin, and nails
Polar molecule
A molecule that has experienced a separation of electric charge, where one side has a slightly negative charge and the other side has a slightly positive charge