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Molecules and cells

Terms in this set (37)

transport, storage, enzyme catalyst, motion, skeletal support, immune protection, nerve impulse transmission and control of metabolism, growth and differentiation
What are the biological roles of proteins?
Protein
What is this - consist of a single chain or several polypeptide chains
alpha carbon, carboxyl group - proton donor, amine group - proton acceptor, hydrogen group, variable R group
Structure of an amino acid
Due to the a.a alpha carbon being asymmetric so it has 4 different functional groups attached - except glycine
How do D and L isomers exist
D isomers have the amine group on the RHS and are found in bacterial cell walls
L isomers have the amine group on LHS and are found in proteins
Describe D and L isomers
aliphatic, hydroxyl, sulfur, aromatic, acids and amides, basic and imino
State the different classifications of aa
Polar, charged R group
Hydrophilic due to the presence at pH 7 of full +ve and -ve charge in R group - what is this
Polar, uncharged R group
Hydrophilic due to the presence of partial charges in pd-pd bonds in non-ionisable R groups at pH 7
if it's hydrophobic
How is an R group non- polar
N terminal residue (NH3+) at LHS
C terminal residue (COO-) at RHS
R group spread evenly over top and bottom of chain
Describe peptide bond formation
Primary structure
what structure of protein is aa sequence
Secondary structure
the aa arrangement in a polypeptide sequence in space
Tertiary structure
3D structure of all atoms in a single chain
interactions between R groups lead to folding
Quaternary structure
3D interaction of subunits in a protein with more than one polypeptide chain
protein structures
alpha helix, beta sheet and triple helix are all examples of what
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