• Quantitative Metrics in Downstream Protein Purification:
• Total Activity (Units): $\text{Total Units} = \text{Activity per ml} \times \text{Total Volume}$.
• Because chromatography, precipitation, and filtration steps inevitably involve mechanical losses and denaturation, total enzyme activity always decreases across successive purification stages.
• Specific Activity (Units/mg protein): $\text{Specific Activity} = \frac{\text{Total Activity}}{\text{Total Protein mg}}$.
• As non-target contaminating proteins are selectively removed, the purity of the enzyme rises, causing specific activity to increase.
• nalysis:
• (Decreases): Correct behavior of total activity during purification.

Correct option: (2) Decreases