Y10 Science atoms, isotopes the nuclear force and rdioactivity basics

2. Structure of the atom nucleus proton neutron electrons

18. The four forces

19. Radiation Radiation : The process of emitting energy in the form of waves or particles. Where does radiation come from? Radiation is generally produced when particles interact or decay. A large contribution of the radiation on earth is from the sun (solar) or from radioactive isotopes of the elements (terrestrial). Radiation is going through you at this very moment! http://www.atral.com/U238.html

31. Background radiation

33. What types of radiation are harmful? Why is ionising radiation harmful? Radiation

36. During the Second World War, two atomic bombs were dropped on Hiroshima and Nagasaki in Japan. Those people who survived the blast were exposed to a large dose of radiation. Such doses caused severe damage to cells all over the body, especially in the skin, blood, bone tissue and gut. WW2 – Hiroshima and Nagasaki Fat Man

37. Many of these people died within a few weeks. Those people who were exposed to a smaller dose recovered from such immediate effects. WW2 – Hiroshima and Nagasaki

40. These effects take longer to become apparent and can be caused by much lower levels of radiation. One of the most important long-term effects of radiation is that of cancer in various parts of the body. Long term effects of Ionising Radiation

41. Uranium miners tended to get lung cancer due to breathing in gases which emitted alpha particles. People who painted the dials of clocks with luminous paint developed oral cancer from using their lips to make points on the brushes. Long term effects of Ionising Radiation

42. Exposure to ionising radiation causes cancer ? The mechanisms for cancer occurring are poorly understood at the moment. One theory is that the ionising radiation affects the DNA material within us – our genetic make-up. Our DNA contains instructions which control the cells. If ionising radiation alters these instructions in the DNA, there is a chance that cancer will develop. Genetic damage can be caused to cells by radiation, including cells which are involved in reproduction.