protein Flashcards
what is a protein
a polymer made from amino acids, carry out number of functions in living organism, can be used to catalyse enzyme, transport for oxygen, storage
what is an amino acid
Made from C,H,O,N,S, contains an amine group- carboxyl group- R group- hydrogen atom- Carbon in middle
describe the structure of amino acid
draw out
what is an r group and how many are there
there are 20- used to abbreviate the different molecules- r group is different in each amino acid
what are amino acids joined together by and what does it form
joined together by condensation reaction to form peptide bonds
what does 2 amino acids make
a dipeptide
what is a polypeptide
3 or more amino acids joined together
what is a protein
1 or more polypeptide chains folded into a complex 3-D shape
how many structures are there in a protein and what are they
4- primary, secondary, teritary, quaternary
describe the primary structure
number, type and sequence of amino acid determined by DNA triplet sequence- the primary structure determines the rest of the protein structure
describe the secondary structure
coiling of primary structure: alpha helix- left hand spiral held by hydrogen bonds between acid and amine group, folding of primary structure= beta pleated sheet- polypeptide zigzags form sheet of antiparallel strands
describe the tertiary structure
further folding/coiling of secondary structure- form 3D shape due to r group, has h-bonds, i-bonds, d.s-bonds, and hydrophobic interactions.
what is a hydrogen bond
a charge between an slightly positive hydrogen and a slightly negative oxygen
what is an ionic bond
a charge between opposite charged ions
what is a disulfide bond
a bond between 2 r groups
