Research Paper on:
Brain Development Research and Sonic Hedgehog Functioning

Unformatted Sample Text from the Research Paper:
within man, himself. The total functioning of the brain and how it operates are still unknown. The critical role that the sonic hedgehog plays in the developing brain is only  now being realized. As a baby develops, the brain in particular is a veritable beehive of activity. During this time the brain is working quickly to segment itself into  highly specialized groups of neurons or brain nuclei, each expressing its own set of genes and having very specific functions. Little is known, however, about how brain nuclei of the  appropriate size, shape and location are generated. Currently, researchers are finding that this process is coordinated by the secretion of a single molecule, Sonic Hedgehog, that operates as a positional  signal. Consider the problem faced by the tiny neurons destined to become part of the cerebral cortex. Because they are developed relatively late in a mammalian brain, billions of these  cells must push and shove their way through dense colonies established by earlier neurons. But of all the problems the growing nervous system must solve, the most daunting is posed  by the wiring itself. After birth, when the number of connections explodes, each of the brains billions of neurons will forge links to thousands of others. First they must spin  out a web of wirelike fibers known as axons (which transmit signals) and dendrites (which receive them). The objective is to form a synapse, the gap-like structure over which the  axon of one neuron beams a signal to the dendrites of another. Before this can happen, axons and dendrites must almost touch. And while the short, bushy dendrites dont have  to travel very far, axons--the heavy-duty cables of the nervous system--must traverse distances that are the microscopic equivalent of miles. Depending on the cells location and proximity to the signaling,