Explain the terms primary and secondary structures of proteins. What is the difference between `alpha`-helix and `beta`-pleated sheet structure of proteins?

Explanation

### Step-by-Step Text Solution

**Step 1: Definition of Primary Structure of Proteins**
The primary structure of a protein refers to the unique sequence of amino acids that are linked together by peptide bonds to form a polypeptide chain. This sequence is determined by the genetic code and dictates the protein's specific characteristics and functions.

**Step 2: Definition of Secondary Structure of Proteins**
The secondary structure of a protein refers to the local folded structures that form within a polypeptide due to interactions between the backbone atoms. These interactions primarily involve hydrogen bonding between the carbonyl oxygen of one amino acid and the amine hydrogen of another, leading to specific structural motifs.

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