Author: Joseph Baxter. Linear, quadratic and exponential functions have different graphs, equations, and characteristics. In this tutorial, compare the shape of linear, quadratic, and exponential curves on a graph, and explore how to identify a function as linear, quadratic, or exponential by examining x- and y-coordinates. (more)
The tier of cells at the back of the retina contains the light receptors, the rods and cones. Rods, which are far more numerous than cones, are responsible for our vision in dim light and are out of commission in bright light.
The human eye contains two kinds of photoreceptor cells; rods and cones. Roughly 125 million of them are intermingled nonuniformly over the retina.(Hecht) The ensemble of rods(each about 0.002 mm in diameter) forms an exceedingly sensitive detector, performing in light too dim for the cones to respond to.