CTET Class I to V 2014 Feb Paper

(c) Some animals awake at night. These animals can see things only in black and white colours. In animal eyes, there are two types of cells, rods and cones. The rods are very sensitive to light but can not detect colors. The cones detect particular range of color. Animals that have adapted to living in the dark tend to have far fewer cones, so that they only see in black and white.