Many human actions are reflex actions.
Which two of the following are examples of reflex actions?
Figure 1 shows how the size of the pupil of the human eye can change by reflex action.

Name one stimulus that would cause the pupil to change in size from Eye X to Eye Y, as shown in Figure 1.
Structure K causes the change in size of the pupil.
Name structure K.
Describe how structure K causes the change in the size of the pupil from Eye X to Eye Y.
Figure 2 shows some structures involved in the coordination of a reflex action.

Describe how the structures shown in Figure 2 help to coordinate a reflex action.