Match the different levels of protein organization with their definition.
levels of organization:
1. primary structure
2. secondary structure
3. tertiary structure
4. quaternary structure
definitions:
a. linear sequence of amino acids in the polypeptide chain
b. three-dimensional structure of a polypeptide
c. highly regular local sub-structures such as α-helix and β-pleated sheet structures
d. three-dimensional structure of a multi-subunit protein
select one:
a. 1-c, 2-d, 3-b, 4-a
b. 1-a, 2-c, 3-b, 4-d
c. 1-d, 2-a, 3-b, 4-c
d. 1-a, 2-b, 3-d, 4-c
e. 1-c, 2-d, 3-a, 4-b