Question

a researcher observes the direct and indirect response of the pupil after stimulation with different intensities of light.
constriction latency
dilatation latency
what was the approximate indirect dilatation latency of the pupil at 10 cd/m²?
a. 0.135
b. 0.185
c. 0.45
d. 0.56

Explanation:

Step1: Identify the relevant graph

We need to look at the "Dilatation Latency" graph since the question is about dilatation latency. The key for indirect response is the dashed line with the specific marker.

Step2: Locate the light intensity of 10 cd/m²

On the x - axis of the "Dilatation Latency" graph, find the point corresponding to 10 cd/m². Then, look at the y - value for the indirect (dashed line) at this x - value.

Step3: Estimate the y - value

From the graph, at x = 10 cd/m² (light intensity), the indirect dilatation latency (dashed line) is approximately 0.185 (looking at the y - axis scale which has values like 0.125, 0.150, 0.175, 0.200, 0.225 and the point for indirect at 10 is between 0.175 and 0.200, closer to 0.185). Option A is 0.135 which is too low, Option C (0.45) and D (0.56) are values from the constriction latency graph (wrong graph) and are too high.

Answer:

B. 0.185