Final answer:
If all the cones in the retina were destroyed, a person would only be able to see in shades of gray, similar to being color blind, with reduced visual acuity particularly in bright light, but could still see shapes and movement in low-light conditions.
Step-by-step explanation:
Vision Without Cones
Cones are the photoreceptor cells in the retina responsible for color vision and the ability to see fine details. If all of the cones in the retina were destroyed by a drug, a person would only be able to see in shades of gray because they would only have rods, which are sensitive to low light but not color. This condition would be similar to being color blind in all lighting conditions. Additionally, detailed vision would be severely compromised, particularly in bright light where cones function best. Rods provide good peripheral vision and are more sensitive than cones in dim light, so the person would still be able to see shapes and movement, especially in low-light conditions. This would also mean that the person's ability to adapt to darkness would remain intact, as rods are active under such conditions.
Effects on Daily Life
Without cones, tasks requiring color discrimination or fine detail work (such as reading or recognizing faces) would become extremely difficult, particularly in bright light. The individual's visual acuity would be greatly reduced, affecting daily activities and potentially making tasks such as driving hazardous. It's essential to note the difference in function between rods and cones, cones being crucial for high-resolution vision and rods for vision under low light conditions.