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Published byDwayne Francis Modified over 9 years ago
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Prologue
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The New Biology Biological View of AIDS Virus HIV causes cells to become factories. Over 25 million dead, over 40 million infected. Scientists working on a vaccine. Growth Hormone Original GH came from pituitary glands of deceased. Currently produced by bacteria A problem of distribution
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Solving Problems Scientific problems are solved by using observations – not feelings. Data is information gained through observation. The scientific method helps us to determine what is reasonable and what is not.
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Solving Problems Testing a Hypothesis: A controlled experiment is designed. The experimental group has one variable changed. Independent vs. Dependent The control group stays the same.
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Evolution: Science at Work A theory explains current observations and predicts new observations. 19 th century biologists noticed that fossils were different from living organisms. Theory of Evolution: species have changed over time in response to changes in their environment.
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Evolution: Science at Work Jean Baptiste Lamarck suggested that life can change. He suggested evolution was a process of adaptation. The more a body part was used the stronger it got and vise versa.
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Evolution: Science at Work A hypothesis is an explanation that is testable through experimentation or observation. If... Then...because... Lamarck’s predictions that acquired characteristics are inherited can not be proven true.
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Evolution: Science at Work British naturalist Charles Darwin developed a theory of evolution that is still in use. Darwin used James Hutton’s hypothesis of uniformitarianism as the basis for his theory. If Earth has such a long history of change – shouldn’t the organisms on it have changed as well?
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The Theory of Natural Selection In 1859 Darwin published the book “The Origin of Species”. He stressed natural selection – organisms best suited for their environment survive – as a means for evolution. Some members of a species have characteristics that enable them to survive.
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The Theory of Natural Selection A species is a group of organisms who can produce viable offspring. Successful organisms pass on their successful characteristics to their offspring. These successful characteristics are referred to as adaptations.
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The Theory of Natural Selection Thomas Malthus: if organisms reproduce at a steady rate – they would outstrip the food supply. Not all organisms live long enough to reproduce because resources are limited. Competition for limited resources drives evolution.
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The Theory of Natural Selection Small differences called variations can either help or hinder members of a population. Natural selection eliminates organisms with variations that are not advantageous.
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The Theory of Natural Selection Good theories lead to logical hypotheses. Darwin’s theory of descent with modification – related organisms share a common ancestor – can be tested. Lamarck and Darwin proposed different theories to explain the same observation.
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Science as a Way of Knowing Characteristics that define science: The natural world can be investigated. Science is based on observations and controlled experiments. The results of the experiments must be repeatable. The findings of science must be refutable – if a hypothesis is not supported by evidence it must be rejected.
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Science as a Way of Knowing Copernicus and Galileo concluded that Earth revolved around the sun. These ideas contradicted scriptures – Galileo was arrested. Rejecting science does not change the science – it merely prevents people from learning and understanding …
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Science as a Way of Knowing Pseudoscience is false science – the research does not meet the definition of science. Creationism is pseudoscience in that the logic behind it cannot be tested with the scientific method.
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Science as a Way of Knowing 5 Questions on research: What is the question? What are the data and how were they obtained? – separate data from opinions. What do the data mean? – does the data support the argument.
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Science as a Way of Knowing 5 Questions on research: Who is reporting the data? – determine credentials and background. Is our knowledge sufficient to answer the question.
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