C1.1 酶與代謝（分子）：练习题

• a.

  To provide energy for endergonic reactions.

• b.

  To increase the activation energy required for a reaction to occur.

• c.

  To decrease the activation energy of a reaction, thereby increasing its rate.

• d.

  To permanently alter the chemical equilibrium of a reaction.

• a.

  The reaction rate will remain constant, as all active sites are saturated.

• b.

  The reaction rate will continue to increase linearly.

• c.

  The reaction rate will decrease due to substrate inhibition.

• d.

  The enzyme will denature, causing the reaction to stop.

• a.

  Both product X and product Y independently activate the enzyme converting A to B.

• b.

  Both product X and product Y competitively inhibit the enzyme converting A to B.

• c.

  Product X inhibits the enzyme converting B to X, and product Y inhibits the enzyme converting B to Y.

• d.

  A high concentration of product X non-competitively inhibits the enzyme converting B to Y.

• a.

  Its activity would be temporarily reduced at pH 7 but fully restored upon return to pH 2.

• b.

  The enzyme would be permanently denatured, leading to a significant loss of activity even after returning to pH 2.

• c.

  The \(K_m\) for its substrate would decrease at pH 7, indicating increased affinity, but \(V_{max}\) would remain unchanged.

• d.

  It would begin to function as an allosteric enzyme at pH 7, gaining new regulatory properties.

• a.

  The sigmoidal curve becomes more hyperbolic, and the apparent affinity for the substrate increases.

• b.

  The \(V_{max}\) value decreases, and the curve shifts to the left.

• c.

  The \(K_m\) value increases, making the sigmoidal curve steeper.

• d.

  The enzyme becomes saturated at lower substrate concentrations, but its cooperativity increases.

先自己写一遍答案，再对照解题步骤。

先自己写一遍答案，再对照解题步骤。