Question

Assertion (A): In compound eyes of cockroach, superposition images are formed.
Reason (R): Absence of retinal sheath in ommatidia.

• A. A and R are true. R is the correct explanation for A.
• B. A and R are true. R is not the correct explanation for A.
• C. A is true. But R is false.
• D. A is false. But R is true.

Hint:

The structure of compound eyes in cockroaches allows them to detect movement and navigate effectively in low-light conditions.

Answer 1

The Correct Option is A

The compound eyes of cockroaches have multiple ommatidia, which are individual optical units that work together to form a complete image. Superposition images are formed when multiple images from these ommatidia overlap, allowing the cockroach to see a broader view, especially in low-light conditions. The key factor for this phenomenon is the absence of a retinal sheath in the ommatidia, which normally would limit the ability to form superimposed images. Without this sheath, light from different ommatidia can combine to form a clearer image, giving the cockroach enhanced vision. This ability to form superposition images is crucial for the cockroach's survival, especially in dark environments.
Final Answer:
A and R are true. R is the correct explanation for A.