How Does It Happen?

 Scientists learn from other scientists  What experiments or tests were already performed  What were the results of these tests  Scientists learn from themselves  What tests have I already performed and what were their results  Then they draw conclusions or possiblities

 Before performing any experiment you must plan, plan, and plan  Write your plan in your laboratory notebook and sketch the equipment that you will use  Make charts to record any data and/or observations  State the idea that you are going to test (hypothesis)

 While the experiment is running, scientists observe continuously  Record ALL data (whether it is what you expected or not)  Even if at first glance the experiment looks like a failure record all observations, it may be a success in another way

 In 1928, the Scottish scientist Alexander Fleming was investigating disease-causing bacteria when he saw that one of his cultures contained an area where no bacteria were growing. Instead, an unknown organism was growing in that area. Rather than throwing the culture in the trash and calling it a failure, Alex investigated the unfamiliar organism and found that it was a type of mold. This mold produced a substance that prevented the growth of many disease bacteria. What he found by questioning the results of a “failed” experiment became the first modern day antibiotic, penicillin.

 Always retest to be sure of those first observations.  Test several times  This is how x-rays were invented  A German scientist Roentgen was trying to investigate cathode rays. He got unexpected results that he knew that cathode rays could not have produced. After further investigation he held his hand between paper and the rays to see if these rays could travel through many things. They, in fact, did travel however they left an outline or a shadow of his bones. Within a year a doctor used these “x-rays” to help set a boys broken arm.

 We know that science is observing, studying, and experimenting to find the nature of things.  Science has two main branches  Social Science  Natural Science  Natural science tries to understand the “nature” or “the whole universe”

Natural Science Life Science: science of living things ZoologyBotany Many Other Branches Physical Science: science of matter and energy Physics: Forces and energy Chemistry: matter and its changes Earth Science: science of earth GeologyMeteorology Many Other Branches

 Life Science or Biology – the science of living things  Botany – the science of plants  Zoology – the science of animals  Ecology – the science of balance in nature  Medicine and agriculture are branches of biology too  Physical Science – the science of matter and energy  Chemistry – the science of matter and its changes  Physics – the science of forces and energy

EEarth Science – the science of earth GGeology – the science of the physical nature and history of the earth MMeteorology – the science of atmosphere and weather

 This classification of science seems like everything fits into its own box  However, there is a problem  As science has progressed, the branches of science have grown out of their little boxes Example – Chemists have begun to explain the workings of chemicals that make up living things, such as DNA. This science is called biochemistry, the study of the matter of living things. Example – The study of the forces that affect the Earth is geophysics, which is both an Earth science and a physical science.

SScientists who do experiments to learn more about the world are practicing pure science (the continuing search for scientific knowledge) EEngineers look for ways to use this knowledge for practical applications TThis application of science is called technology EExample – Scientists who practice pure science want to know how certain kinds of materials, called superconductors, conduct electricity with almost no loss in energy. Engineers focus on how that technology can be used to build high-speed computers.

 Technology and science depend on one another  For instance, scientists did not know that tiny organisms such as bacteria even existed until the technology to make precision magnifying lenses developed in the late 1600s.