Question

1. many factors can affect the rate of enzyme action. explain the effects of each factor listed here.

a. initial concentration of substrate
b. ph
c. temperature

1. recall that enzymes are globular proteins. why can extremes of ph or very high temperatures affect enzyme activity?
2. name a human enzyme that functions well in ph 2. where is it found?

Explanation:

27.a.

Increasing substrate concentration initially increases reaction rate as more enzyme - substrate complexes form. But when enzymes are saturated, rate levels off.

27.b.

Each enzyme has an optimal pH. Deviations from it can disrupt ionic and hydrogen bonds in the enzyme's structure, altering its active - site shape and reducing activity.

27.c.

Increasing temperature increases molecular motion, initially increasing reaction rate. But above the optimal temperature, the enzyme can denature, losing its structure and activity.

28.

Extremes of pH or high temperatures can break the weak bonds (hydrogen bonds, ionic bonds) that maintain the enzyme's three - dimensional structure. This causes denaturation, altering the active - site shape so the substrate can no longer bind effectively.

29.

Pepsin is a human enzyme that functions well at pH 2. It is found in the stomach.

Answer:

27.a.

Increasing substrate concentration initially increases enzyme - action rate until enzyme saturation is reached.

27.b.

Each enzyme has an optimal pH; deviations reduce activity by altering structure.

27.c.

Increasing temperature increases rate until optimal; higher temperatures cause denaturation and reduced activity.

28.

Extremes of pH or high temperatures break bonds in enzyme structure, causing denaturation and reducing activity.

29.

Pepsin; stomach.