Question

question 29
predict how a fever of 40°c (104°f) would affect enzyme activity.
a the enzymes would be unaffected by the temperature increase, as long as ph remains the same.
b the activity of the enzymes would slow down dramatically.
c the enzymes would catalyze more reactions due to the higher temperature.
question 30
when the shape of an enzymes active site is mutated due to a change in ph or temperature, preventing the substrate from binding, the enzyme is _.
a acidic
b organic
c denatured

Explanation:

Question 29

Enzymes are proteins. High temperatures (like \(40^{\circ}C\) which is above normal body temperature of around \(37^{\circ}C\)) can denature enzymes. Denaturation changes the shape of the enzyme's active site. When the active - site shape is altered, the enzyme cannot bind to its substrate effectively.

• Option A: Enzymes are affected by temperature changes even if pH is constant. So, this option is incorrect.
• Option B: High temperature causes denaturation, not just a slow - down. A slow - down would imply the enzyme is still functional to some extent in its original form, but denaturation means a more severe structural change. So, this option is incorrect.
• Option C: At very high temperatures (above the optimal temperature for the enzyme), enzymes denature. Denatured enzymes cannot catalyze reactions. At temperatures slightly above the optimal, there might be a small increase in reaction rate due to increased molecular motion, but \(40^{\circ}C\) is high enough to cause significant denaturation in many human enzymes. So, this option is incorrect.

• Option A: "Acidic" refers to the pH property (a solution with a pH less than 7). It does not describe the state of an enzyme when its active site is mutated.
• Option B: "Organic" refers to compounds containing carbon (in a biological context, often carbon - based compounds like carbohydrates, lipids, proteins, nucleic acids). It is not related to the state of an enzyme when its active site is altered.
• Option C: Denaturation is the process by which proteins (enzymes are proteins) lose their native (natural) three - dimensional structure (including the shape of the active site) due to factors like changes in pH or temperature. When denatured, the enzyme cannot bind to its substrate (as the active site shape is changed).

Answer:

None of the options A, B, and C are correct. However, if we assume a less - than - perfect understanding (in a basic biology context where the focus is on denaturation effects), the most reasonable incorrect - but - closest - to - a - common - misunderstanding option is that the activity of the enzymes would slow down dramatically (Option B) compared to the other options which have more fundamental flaws (A ignores temperature effect on enzymes, C assumes no denaturation at a relatively high temperature). But in reality, at \(40^{\circ}C\), for many human enzymes, denaturation occurs which is more than just a'slow - down'.

Question 30