Biochemistry - proteins Flashcards
what are proteins?
polymers of amino acids
how do proteins/ amino acids differ ?
the R group
what bonds are present in primary structure of proteins?
peptide bonds
what is the primary structure ?
a sequence of amino acids
what is the secondary structure?
alpha helices and beta pleated sheets
what is the tertiary structure?
further folding of the polypeptide chain
what is the quaternary structure?
more than two polypeptide chain bonded together
what are fibrous proteins ?
- structural proteins
- secondary structure
- insoluble
e.g. keratin and collagen
what are globular proteins ?
- tertiary or quaternary structure
- metabolic function
-soluble in water
e.g. enzymes, hormones
what is the test for proteins ?
biuret test
colour change from blue to purple
what bonds are present at the secondary structure ?
peptide and hydrogen
what bonds are present at the tertiary structure?
peptide, hydrogen, disulphide bridge, hydrophobic interactions, and ionic bonds
what bonds are present at the quaternary structure?
hydrogen, ionic bonds, or hydrophobic interactions
can you…?
draw the general formula for amino acids and recognise amino (basic), carboxylic
(acidic) and R (variable) groups
what are the function of proteins?
help in metabolism, provide structural support, enzymes, carriers, and hormones
