One of the first things that most designers forget about CSS descendant selectors is that they are flexible. When CSS defines a descendant, it doesn't care whether the tag in question is the direct child, the grandchild, or some great-great-great-descendant of the initial element.
From the retina, visual information passes onto the bipolar cells and then to the optic nerve's ganglion cells. The optic nerve, which begins at the retina, is the sole visual pathway to the brain. Light information is conveyed as an electrical action potential through the neurons.
Information is coded in the brain as patterns of electrical impulses that are transmitted along nerve processes. These impulses are passed from one neuron to the next primarily at chemical synapses where the electrical event is converted to the release of a neurotransmitter substance that activates the next neuron in the pathway.