chapter one- intro to biology
DESCRIPTION
Chapter One Lecture for Lab BiologyTRANSCRIPT
Ch. 1 The Science of Biology
• What is science?• Science: an organized way of using
evidence to learn about the natural world.
• The goal of science is to investigate and understand the natural world and to use those explanations to make useful predictions.
• Thinking like a scientist: begins with observations which gives data,
qualitative or quantitative (numbers)
• Next, questions are asked and answers are considered, which leads to forming a hypothesis: a proposed scientific explanation for data which can be tested!!!
• Scientists collaborate and share data and discuss experiments.–Designing an experiment:
1. Ask a question2. Form a hypothesis3. Set up a controlled experiment
(one variable) 4. Record and analyze data5. Draw a conclusion6. Repeat the experiment!!!!
• Manipulated variable: the one thing that changes in an experiment. (Everything else is the same.)
• Responding variable: the item that changes as a result of the manipulated variable.
• Example: Redi’s experiment
If possible, experiments should have only one manipulated variable, everything else should be kept the same or controlled.
Why are controlled experiments sometimes impossible?
Developing Theories• If a hypothesis is supported by
repeated experimentation, it may become a theory.–A theory is a well-tested explanation
for a broad set of observations.–A theory may need to be changed at
some point in the future to explain new observations or experimental results.
Scientific Laws• A scientific law is a concise
statement that summarizes the results of many observations and experiments. • A scientific law doesn’t try to
explain. That explanation requires a theory.
The Scientific Method
How Science Works
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In reviewHypothesis- an explanationExperiment- tests hypothesisTheory- an explanation that has been verified
by so many different experiments that we agree it is TRUTH.
Scientific Law- states what happens
LAW- Boats disappear on the horizonOld hypothesis- the world is flatCurrent theory- the world is round
Biology: the study of life• Characteristics of living things:–Made of cells–Reproduce (sexual or asexual)–Universal genetic code (DNA)–Grow and develop–Obtain and use material and energy–Respond to their environment–Maintain a stable internal environment
(homeostasis)–Change over time (evolve)
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Figure 1-19 on page 21
LEVELS OFBIOLOGICALORGANIZATION
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THE METRIC SYSTEM
A compound light microscope allows
light to pass through an image and uses two
lenses to form an image.
You can see tiny stuff!
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An electron microscope uses
beams of electrons to form an image.
1000x more powerful!You can see parts of cells & molecules.
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