Consider the following : Enzymes and protein can be corelated with each other in the following ways 1. All proteins are enzyme. 2. All enzymes are protein. 3. All enzymes are not protein. 4. All proteins are not enzyme. Which of the above are correct ?

The correct answer is Option 2 (2 and 4 only). This is based on the fundamental biochemical relationship between proteins and enzymes.

• Statement 2 is correct: Traditionally, in biological systems, all enzymes are chemically categorized as globular proteins. They are long chains of amino acids folded into specific three-dimensional structures that facilitate catalytic activities. While "ribozymes" (RNA catalysts) exist, in the context of standard biological classification used in competitive exams, enzymes are considered proteins.
• Statement 4 is correct: While enzymes are proteins, the reverse is not true. Proteins serve diverse functions beyond catalysis, including structural roles (collagen, keratin), transport (hemoglobin), and hormonal regulation (insulin). Therefore, not all proteins act as enzymes.

Why others are incorrect: Statement 1 is false because many proteins have non-enzymatic functions. Statement 3 contradicts the established biological principle that enzymes are proteinaceous in nature. Thus, only statements 2 and 4 accurately define the correlation.