AP BIOLOGY

LABORATORY REVIEW

MOLECULAR BIOLOGY

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
As temperature increases toward the optimal level, the kinetic energy of the enzyme and substrate ____, resulting in ____ collisions.
A
increases, more frequent
B
increases, less frequent
C
decreases, more frequent
D
decreases, less frequent
Explanation: 

Detailed explanation-1: -Higher temperature generally causes more collisions among the molecules and therefore increases the rate of a reaction. More collisions increase the likelihood that substrate will collide with the active site of the enzyme, thus increasing the rate of an enzyme-catalyzed reaction.

Detailed explanation-2: -Answer. As temperature increases, the kinetic energy contained within substrate and enzyme molecules also increases. This means that they move faster, and the substrates are more likely to successfully collide with the enzyme’s active site.

Detailed explanation-3: -As the temperature increases so does the rate of enzyme activity. An optimum activity is reached at the enzyme’s optimum temperature. A continued increase in temperature results in a sharp decrease in activity as the enzyme’s active site changes shape. It is now denatured.

Detailed explanation-4: -At low temperatures the enzyme activity will be slow, however, as the temperature increases the enzymes gain kinetic energy (they move around more). This increases the amount of successful collisions with the substrate molecules, meaning that more enzyme-substrate complexes are made.

Detailed explanation-5: -Temperature: Raising temperature generally speeds up a reaction, and lowering temperature slows down a reaction. However, extreme high temperatures can cause an enzyme to lose its shape (denature) and stop working. pH: Each enzyme has an optimum pH range.

There is 1 question to complete.