Question

question 6 · 1 point
what happens to most biological enzymes when the temperature is about 50°c?
select the correct answer below:
enzymes work most efficiently.
enzymes become denatured and begin catalyzing reactions.
enzymes become denatured and stop being able to catalyze reactions.
this is too cold for most biological enzymes, so they catalyze reactions at too slow of a rate.

Explanation:

Enzymes are proteins. High temperatures (such as \(50^{\circ}C\)) disrupt the weak bonds (like hydrogen bonds) that maintain the enzyme's three - dimensional structure. When the structure is disrupted (denatured), the active site (where the substrate binds) is no longer in the correct shape. Since the enzyme - substrate interaction is highly specific (lock - and - key model or induced fit model), a denatured enzyme cannot bind to its substrate properly and thus stops catalyzing reactions.

• Option "Enzymes work most efficiently" is wrong because most biological enzymes have an optimal temperature (usually around \(37^{\circ}C\) for human enzymes), and \(50^{\circ}C\) is above the optimal for most and leads to denaturation.
• Option "Enzymes become denatured and begin catalyzing reactions" is incorrect as denaturation impairs, not enhances, catalytic activity.
• Option "This is too cold for most biological enzymes..." is wrong because \(50^{\circ}C\) is a relatively high temperature, not a cold one.

Answer:

Enzymes become denatured and stop being able to catalyze reactions.