Why does the eyecup of the flatworm only detect light and dark, not images?
A)There are too few photoreceptors.
B)There is no lens.
C)The eyecup is lined by a pigmented epithelium.
D)Flatworms do not have a brain.

Question

Quizplus · Accepted Answer

The eyecup of the flatworm does not have a lens to focus light onto photoreceptors, which means that it cannot form a clear image. Rather, it can only detect the presence or absence of light, allowing the flatworm to distinguish light from dark environments.

Why Does the Eyecup of the Flatworm Only Detect Light