Frog zoology - Nervous System - Encyclopedia II

The frog has a highly developed nervous system which consists of a brain, spinal cord and nerves. Many parts of the frog's brain correspond with those of humans. The medulla regulates respiration, digestion, and other automatic functions. Muscular coordination and posture are controlled by the cerebellum. A frog has a very small cerebrum; that of a man is much larger (relatively). In humans, the cerebrum runs many important life processes.

Frogs have ten cranial nerves (nerves which pass information from the outside directly to the brain) and ten pairs of spinal nerves (nerves which pass information from extremities to the brain through the spinal cord). By contrast, humans have twelve cranial nerves and 30 pairs of spinal nerves.

The frog has crude eyes and two nostrils for smell. The nostrils have complex valves, but no long nasal passages. Frogs do not have external ears; the eardrums (tympanic membranes) are directly exposed. As in humans, the ear contains circular passages which help control balance and orientation.

Adapted from the Wikipedia article "Nervous System", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki/Main_Page