Final answer:
Dirk's difficulty seeing in low-light conditions is likely due to malfunctioning rods in his retina, which are responsible for night vision. The cornea, primarily responsible for focusing light onto the retina, usually does not cause issues with night vision when damaged.
Step-by-step explanation:
If Dirk has difficulty seeing in low-light conditions or at night after a beer brewing accident, it's likely that his rods are malfunctioning rather than his cornea. Rods are photoreceptor cells in the retina of the eye that are responsible for vision at low light levels. They are not involved in color vision, which is a function of cone cells. Difficulty seeing in dim light, a condition known as night blindness or nyctalopia, can be a symptom of issues with these cells or with other parts of the visual pathway that handle low-light information.
This condition typically does not involve a cornea problem. The cornea's primary role is to focus light onto the retina, and while it can affect vision clarity if damaged or malformed, it usually does not cause issues with night vision. Instead, conditions like cataracts, which involve cloudiness in the lens, or retinal problems could lead to symptoms like Dirk's, but the scenario specifically suggests rod malfunction in the retina for night vision difficulties.