Gradual changes in the frequency of diseases over long periods are known as SECULAR TIME TRENDS. For example, the rate of mortality in USA due to coronary heart diseases over a period of time. Onset of puberty in girls is also a secular time trend.
Secular time trend is also referred as Secular Variation and Secular Drift.
Answer: Louis Pasteur
Louis Pasteur in 1860s, proposed germ theory. The theory was based upon the fact that diseases are caused by the microorganisms.He was officially the first to publish his work.
The parasympathetic nervous system <span>conserves energy as it slows down heart rate, increases intestinal and glandular activity, and relaxes the sphincter muscles of the gastrointestinal tract. It gets the nickname "rest and digest" for doing exactly so. Typically most active when sleeping, however is also the explanation for post-prandial fatigue, or being tired after eating (especially a large meal).</span>
Myelin sheaths, which cover the axon of the nerve cells in the brain and spinal
cord, prevents the electric current from dissipating from the axon.
Destroying the <span>myelin sheaths impairs the
conduction of signals on the affected nerves, causing damage in
every function that the nerve is involved, in this case will affect movements and vision.</span>