Question

1. as the temperature increases from 30 c to 50 c, the rate of action of this enzyme... a. remains the same. b. increases steadily. c. decreases steadily. d. increases then decreases.

Explanation:

Enzyme activity generally increases with temperature up to an optimal temperature (often around 37°C for human enzymes, but for many enzymes, the optimal can be in the range where 30 - 50°C might still be below or approaching the optimal before denaturation starts). However, if we assume the enzyme's optimal temperature is above 50°C or in a range where from 30 - 50°C it's still increasing (or if it's a thermophilic enzyme, but more commonly, for typical enzymes, as temperature increases within a reasonable range below denaturation, activity increases steadily until the optimal, then decreases. But the question is from 30 to 50. If we consider that maybe the optimal is above 50, then the rate would increase steadily. But wait, actually, many enzymes start to denature above a certain temp, but the options: if we think about the general trend before denaturation, as temp increases (within the range where enzyme is not denatured), the rate of reaction (enzyme - catalyzed) increases because kinetic energy of molecules increases, more collisions, more effective collisions. So from 30 to 50, if 50 is below the denaturation temp, the rate increases steadily. But wait, maybe the answer is d? No, wait, no—wait, the question is about enzyme activity with temperature. Wait, maybe I got it wrong. Wait, the options: a) remains same, b) increases steadily, c) decreases steadily, d) increases then decreases. Wait, actually, the correct trend for enzyme activity with temperature is that it increases with temperature until the optimal temperature, then decreases as the enzyme denatures. But the temperature range here is 30 to 50. If the optimal temperature of the enzyme is, say, 40 - 50, then from 30 to 50, it might increase then decrease (if 50 is above optimal). But if the optimal is above 50, then it would increase steadily. But in many standard questions, if the range is from below optimal to above optimal, but maybe in this case, the intended answer is d? Wait, no, maybe I made a mistake. Wait, let's recall: Enzyme activity vs temperature: at low temp (below optimal), activity increases with temp (more kinetic energy, more substrate - enzyme collisions). At high temp (above optimal), activity decreases as enzyme denatures (active site changes). So if the temperature goes from 30 to 50, and if the optimal is, say, 40, then from 30 to 40 it increases, from 40 to 50 it decreases—so the rate increases then decreases (option d). But maybe the question's enzyme has an optimal in that range. So the correct answer is d. increases then decreases. Wait, but maybe the original question's context is different. Wait, the options: d is "increases then decreases". So the answer should be d.

Answer:

d. increases then decreases