proteins Flashcards
what are proteins made from?
amino acid monomers - they join through a condensation reaction forming a peptide bond
how is a dipeptide made?
by joining two amino acids
what are the four structures of proteins?
primary, secondary, tertiary and quaternary structure
what is the primary structure?
> this is the amino acid chain or polypeptide and is determines by the DNA sequence
what is the secondary structure?
> this is when the polypeptide is folded and hydrogen bonds form between the polypeptide
two main types are alpha helices and beta pleated sheets
what is the tertiary structure?
> this involves the further folding of the secondary protein (polypeptide)
protein becomes functional and 3D
bonds formed: hydrogen, ionic and disulfide bonds
what is the quaternary structure?
> this is where multiple polypeptide chains are joined together
what are the two types of protein?
globular and fibrous
describe globular proteins
> round and ball shaped
have metabolic functions
example - haemoglobin
describe fibrous proteins
> long and narrow
have a structural function
example - collagen, keratin
what is the test for proteins?
biuret test
