Chest pain is always an alarming symptom since it usually raises the fear of heart disease. And because chest pain may indeed be a sign of angina or of some other heart problem, it is always a good idea to have it checked out. But heart disease is only one of the many types of conditions that can produce chest pain.
Concept 27 Mutations are changes in genetic information. Hermann Muller received the 1946 Nobel Prize in Physiology or Medicine for his work on mutations induced by X-rays. Seymour Benzer used genetics to prove that mutations were caused by changes in the DNA sequence.
This Plum Pudding model was incorrect. In a later ingenious experiment, Millikan was able to find the electron charge and from the charge to mass ratio. This meant the mass of the electron was extremely small, 9.11 x 10 -31 kg. Now by small we mean that it is about 1800 time smaller than the smallest atom, the H atom. Hence Thomson had discovered a new particle.