Final Answer:
Night blindness refers to the difficulty or inability to see in low-light conditions. Improvement of vision in dim light is known by the term "Night blindness" (Option 4).
Step-by-step explanation:
This condition is often caused by a deficiency of vitamin A, which plays a crucial role in the function of rhodopsin, a pigment in the rods of the retina responsible for low-light vision. In dim light, the eye relies more on rod cells than cone cells. Rod cells are highly sensitive to light and are responsible for vision in low-light conditions. When there is a deficiency of vitamin A, the regeneration of rhodopsin is impaired, leading to decreased sensitivity to dim light and resulting in night blindness.
The process involves the phototransduction pathway, where light stimulates the rhodopsin molecule in rod cells, initiating a cascade of events that ultimately generate nerve impulses to the brain for visual perception. Without sufficient vitamin A, the regeneration of rhodopsin is hindered, leading to a reduced ability to detect light in low-lit environments. Therefore, night blindness specifically denotes compromised vision in dim light conditions due to the deficiency of vitamin A and the consequent impact on the functioning of rod cells in the retina.
In conclusion, the term "Night blindness" accurately describes the impairment of vision in dim light, highlighting the importance of adequate vitamin A for the proper functioning of the visual system, particularly in low-light settings.