MedLinks for PHY  2054   Physics II,     Spring 2002

Data compiled by Prof.   Bernard F. Whiting

Lou Gehrig's Disease:

Lou Gehrig's Disease (also called ALS) is characterized by the progressive degeneration of motor cells (neurones which control voluntary movement) in the brain and spinal cord. As the motor nerves gradually degenerate and die, the muscles they are attached to can no longer receive nerve impulses, and they begin to atrophy, or waste away. ALS patients normally retain their full intellectual power and intelligence, since motor neurons have little impact on cognitive aspects of the nervous system. For further information, check out the ALS/MND Alliance homepage.

Multiple Sclerosis:

While the precise cause of Multiple Sclerosis (MS) is not yet known, it appears that a number of factors in combination are probably responsible. It is now generally accepted that MS involves an abnormal immune response directed against the central nervous system. In MS patients, the destruction of mylin, the fatty sheath which surrounds and insulates nerve fibres, causes nerve impulses to be slowed or halted. It is suspected, but as yet unproven, that childhood exposure to certain viruses may be a triggering factor in the eventual onset of MS. For further information, go to the information page of the National MS Society.

DNA Fingerprinting:

Every strand of DNA has pieces that contain genetic information for controlling an organism's development (exons) and pieces that, apparently, supply no relevant genetic information at all (introns). Although the introns may seem useless, it has been found that they contain repeated sequences, called Variable Number Tandem Repeats (VNTRs), which are unique to the individual. Each person's VNTRs come only from the genetic information donated by his or her parents. DNA fingerprinting is a sophistocated laboratory technique which has been developed to help characterize individuals by their VNTRs In one of the steps, a process called gel electrophoresis is used, which separates DNA fragments in an external electric field, on the basis of their mass. For further information, look at the Basics of DNA Fingerprinting.


A beating heart is vital to the survival of every highly-developed living organism. The rhythm of a heartbeat relies on the propagation of electrical impulses through the various heart muscles, and irregularities ensue if any part of that process is delayed or obstructed. The relative timing between particular pulses provides an enormous amount of non-invasive diagnostic information about the condition and function of the heart. An electrocardiogram, better known as an ECG or EKG, is a test used to record the electrical activity of the heart. From this test, much can be learned about the heart rhythm and the condition of the heart's chambers (particulary if they are enlarged). A thorough exposition of the techniques used to interpret an ECG and diagnose abnormalities can be found at the ECG Learning Center.

Devices and Instrumentation:

Nerve Locators ECG Simulators