When a person enters a dark room, in the rods of his eyes:
1. cGMP levels are high.
2. cGMP levels are low.
3. G protein is degraded.
4. An influx of Ca2+ ions is prevented.
A person is wearing spectacles with concave lenses for correcting vision. While not using the glasses, the image of a distant object in his case will be formed:
1. on the blind spot
2. behind the retina
3. in front of the retina
4. on the yellow spot