Question

examine the ph data in tables 1 and 2.
table 1: human organs and average ph
organ ph
stomach 1 - 3
intestine 6 - 8
mouth 6 - 8
table 2: common enzymes/substrates and optimum ph
enzyme optimum ph substrate
pepsin 1 - 2 protein
lipase 4 - 5 lipids
amylase 7.2 - 7.4 starch
what can be inferred about the effectiveness of enzymes?
enzymes have specific substrates, so they work best within a small, specific range of ph.
enzymes do not have specific substrates and work best in any ph.
enzymes do not have specific substrates, so they work best within a small, specific range of ph.
enzymes have specific substrates and work best in any ph.

Explanation:

1. Analyze enzyme - substrate specificity: From Table 2, Pepsin acts on Protein, Lipase on Lipids, and Amylase on Starch, showing enzymes have specific substrates.
2. Analyze pH optima: Pepsin has an optimum pH of 1 - 2, Lipase 4 - 5, and Amylase 7.2 - 7.4. Each enzyme has a small, specific pH range for optimal activity.
3. Eliminate other options:

• Option B is wrong as enzymes do have specific substrates and don't work best in any pH.
• Option C is wrong because enzymes do have specific substrates.
• Option D is wrong as enzymes don't work best in any pH, they have specific pH ranges.

Answer:

A. Enzymes have specific substrates, so they work best within a small, specific range of pH.