The most likely result is that the enzyme will no longer be able to catalyze the reaction with its substrate.

Direct answer (in question style)

If the shape of the enzyme changes (especially its active site):

The enzyme will no longer be able to catalyze the reaction with the substrate.

This corresponds to answer choice:

  • B / G: “The enzyme will no longer be able to catalyze the reaction with the substrate.”

Why this happens (short explanation)

Enzymes work like a lock-and-key (or “induced fit”) with their substrates:

  • The active site of the enzyme has a specific 3D shape.
  • Only a substrate with a matching shape can bind and react.

If environmental conditions (like temperature or pH) change the enzyme’s shape, the active site may no longer match the substrate:

  • The substrate usually does not change its shape to match the enzyme.
  • Without proper binding, the enzyme–substrate complex cannot form.
  • As a result, the enzyme cannot catalyze the reaction, effectively becoming denatured.

Quick imagined example

Imagine sucrase, the enzyme that breaks down sucrose (table sugar):

  1. At normal body temperature, its active site fits sucrose and breaks it into glucose and fructose.
  2. If you heat it too much, the enzyme’s structure unfolds and the active site is distorted.
  3. Now sucrose no longer fits, so the reaction stops — the enzyme can’t catalyze it anymore.

TL;DR

Changing an enzyme’s shape (by altering environmental conditions) usually means it loses its ability to bind the substrate and catalyze the reaction.