Concept explainers
RECALL Match the following statements about protein structure with the proper levels of organization. (i) Primary structure (ii) Secondary structure (iii) Tertiary structure (iv) Quaternary structure
(a) The three-dimensional arrangement of all atoms
(b) The order of amino acid residues in the polypeptide chain
(c) The interaction between subunits in proteins that consist of more than one polypeptide chain
(d) The hydrogen-bonded arrangement of the polypeptide backbone.
Interpretation:
The statements about protein structure are to be matched with the level of organization.
Concept Introduction:
The structure of protein is a three-dimensional arrangement of atoms in an amino acid-chain molecule.
There are four levels of organization in the protein structure, namely primary structure, secondary structure, tertiary structure and quaternary structure.
Answer to Problem 1RE
Solution:
a) Tertiary Structure.
b) Primary Structure
c) Quaternary Structure.
d) Secondary structure.
Explanation of Solution
Explanations:
The three-dimensional structure of protein is the tertiary structure. Tertiary structure consists of one polypeptide chain and one or more secondary protein structures.
The primary structure is a one-dimensional first step in defining the
A protein consists of multiple polypeptide chains called subunits which interact with each other through non-covalent bonds.
The secondary structure has repetitive interactions resulting from hydrogen bond formation between the amide and carbonyl group of the peptide backbone.
There are four levels of organization in proteins, namely primary, secondary, tertiary and quaternary, based on the arrangement of the atoms.
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Chapter 4 Solutions
Biochemistry
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